A ute canopy door that drops while you are loading gear, or a machinery lid that will not stay safely overhead, is not a problem to solve by fitting a stronger standard strut. The first question is: can gas springs lock open? Yes, but only when the strut is specifically designed with a locking function. A normal gas strut can support an open lid. It cannot be relied on as a positive lock.

Can Gas Springs Lock Open?

Standard gas springs use compressed nitrogen to extend the rod and assist with lifting. Once the lid, hatch or panel reaches its open position, the strut continues to apply force. If the gas force, mounting geometry and load are correctly matched, the assembly will remain open under normal conditions.

That is support, not locking.

A conventional gas strut has no internal mechanism that mechanically prevents it from compressing. Wind, vibration, a change in load angle, someone leaning on the panel, or a loss of gas pressure can allow the lid to move. This distinction matters on heavy toolbox lids, access doors, machine guards, marine hatches and overhead panels where unexpected movement can damage equipment or injure someone.

A locking gas spring is different. It incorporates a mechanism that holds the rod in a selected position, either at full extension or at various points through its stroke. The lock is released by a pin, cable, lever or remote release arrangement, depending on the strut design and application.

Holding force is not a safety lock

A gas strut may feel firm when you push down on an open lid, particularly when it is new. That does not mean it is locked. Gas pressure changes with temperature, and all gas springs lose pressure gradually over their service life. Opening force also depends heavily on the mounting angle. A strut can hold a lid well near the middle of its travel yet provide less effective support at the fully open position.

For this reason, do not treat an ordinary gas strut as the sole safety restraint for a raised load. If positive retention is required, specify a locking strut or include a separate mechanical stay, prop, latch or locking pin.

The main ways to keep a panel open

The right option depends on whether the panel only needs to stay open at one position, whether it needs adjustable positioning, and whether the load presents a safety risk.

Extension-locking gas springs

An extension-locking strut locks when it reaches full extension. It is a practical choice where a lid or door has one defined open position, such as a canopy window, service hatch, storage compartment or equipment enclosure.

Some designs use a mechanical locking sleeve or similar arrangement that engages at the end of the stroke. These provide clear positive retention at full open. Release arrangements must be positioned so the operator can safely support the load while disengaging the lock.

Position-locking gas springs

Position-locking, sometimes called lockable, gas springs can hold at a chosen point in their stroke. They are useful for adjustable seats, medical or industrial equipment, display lids and access panels that need more than one working height.

There are two broad behaviours. Rigid locking designs have very little movement once locked. Elastic locking designs may allow a small amount of compression under load before holding. This small movement is acceptable in some adjustment applications but may not be appropriate where the panel must remain completely fixed.

The release system also needs consideration. A direct push-button release may suit a small cabinet. A cable release or linked mechanism may be required where the strut is difficult to reach or where two struts need to release together.

Mechanical stays, props and locking hinges

For large, high-risk or high-vibration applications, a mechanical support is often the better answer. A folding prop stay, telescopic stay, locking hinge or removable pin provides a visible physical restraint that does not depend on internal gas pressure.

Gas struts can still be fitted to take most of the lifting effort, while the mechanical device carries the safety function. This combination is common on heavy machinery covers, marine lockers, agricultural equipment and large fabricated doors.

When a locking strut is the right choice

A lockable gas spring makes sense when the operator needs a controlled opening action plus a dependable hold-open position. Common examples include overhead doors on service bodies, caravan storage lids, plant access covers, machinery enclosures, large cabinets and adjustable seating.

It is particularly useful when a loose prop would be inconvenient, likely to be misplaced or hard to use in a confined area. A properly selected locking strut can make routine access faster while reducing the chance of a panel closing unexpectedly.

There are limits. A locking gas spring should not automatically be selected for a load that could cause serious injury if it falls. Heavy access panels, frequently used maintenance covers and equipment subject to shock loading may need an engineered secondary restraint. The required solution depends on the panel mass, centre of gravity, opening angle, use frequency and the consequences of failure.

What to specify before ordering

Replacing a standard strut with a lockable version is not always a direct swap. Locking units can have different body dimensions, release clearances, mounting requirements and force characteristics. The existing brackets may need repositioning to achieve the right opening angle and locking point.

Before selecting a strut, record the following details:

• Extended length measured centre-to-centre between the mounting points
• Compressed length and usable stroke
• Existing end fittings, including ball sockets, eyelets, clevises or brackets
• Force rating in newtons, if marked on the current strut
• Panel weight, dimensions and approximate centre of gravity
• Mounting positions when the panel is fully closed and fully open
• Required locking position and preferred release method
• Exposure to dust, salt spray, washdown, heat, vibration or corrosion

Photos of the current installation are also valuable. They show bracket orientation, clearance issues and whether the strut is working close to its travel limits. For custom applications, these measurements allow a strut specialist to check the leverage through the full opening arc rather than simply matching the force printed on an old unit.

Installation details that affect lock performance

Correct geometry matters as much as the strut itself. The lock must engage at the intended open position without the strut reaching a hard internal stop before the lid does. The release control must remain accessible and should not foul on hinges, frames, stored equipment or wiring.

Mount the strut in the manufacturer-recommended orientation. Many conventional gas struts are installed with the rod pointing down when closed so internal oil can lubricate the seal. Locking gas springs may have specific orientation requirements, particularly where the locking valve or release mechanism is involved.

Use brackets and fasteners rated for the load. A strong strut attached to a light bracket can pull the bracket out of sheet metal or distort a lid over time. On wide or flexible panels, two matched struts may be needed to prevent twisting. If two locking struts are used, make sure both units engage and release consistently.

Never drill into, heat, bend or depressurise a gas strut. A bent rod, damaged seal or altered fitting can cause failure and may void the product warranty.

If a standard gas strut suddenly seems locked

An ordinary gas strut that will not compress is not necessarily working as intended. Check for a bent rod, seized end fitting, misaligned bracket, foreign material around the rod or a panel that is binding at the hinges. Do not force it closed with excessive leverage, as this can damage the mounting points or cause the strut to release unpredictably.

Likewise, a strut that no longer holds open is usually losing gas pressure or is no longer correctly matched to the load. Replacing it with a higher-force unit without checking the geometry can make the lid difficult to close and overload the hinges. Measure first, then select the appropriate force and locking method.

For a replacement or a custom locking arrangement, Gas Struts can assess the dimensions, force, fittings and operating conditions to help identify a suitable option. The best hold-open system is the one that supports the load properly, locks only where required, and gives the operator a safe, repeatable way to release it.

A failed canopy strut, plant access door or toolbox lid does not always need a like-for-like replacement. Gas spring alternatives can be the right answer where the load is unusually heavy, the motion must be powered, the environment is harsh, or the lid only needs to stay open rather than lift smoothly. The key is choosing a system that manages the actual load, mounting geometry and safety requirements of the application.

A gas strut combines lifting force, controlled extension and damping in one compact unit. That makes it hard to beat for many vehicle, caravan, marine, cabinet and machinery applications. Alternatives can solve specific problems, but they also introduce compromises in space, operating effort, cost, installation or maintenance.

When gas spring alternatives make sense

Before changing hardware, establish why the current arrangement is not working. A lid that falls may have worn struts, but it may also have changed weight after a spare wheel, tool rack, lining or accessory was fitted. A hatch that is difficult to close may have struts with too much force, incorrect mounting points or the wrong extended length.

An alternative system is worth considering when the application needs one of the following: positive mechanical locking, powered movement, very long travel, operation in extreme temperatures, high cycle life, or support for a load that changes significantly through its travel. It may also suit installations where a standard gas strut cannot be mounted at the required angle or where there is insufficient side clearance for a cylinder.

For most replacement jobs, however, a correctly specified gas strut remains the simplest and most economical solution. Replacing it with a different mechanism simply to avoid measuring the existing part can create a more difficult installation.

Mechanical compression and extension springs

Coil springs are among the most familiar gas spring alternatives. Compression springs resist being squeezed, while extension springs pull when stretched. Both can be used to offset a lid, door, guard or seat base.

Their main advantage is simplicity. Springs do not rely on pressurised gas, and a quality spring can handle repeated cycling in hot, cold or dirty conditions. They can also be fitted where a long gas strut barrel would foul adjacent equipment.

The limitation is force control. A coil spring changes force substantially as it compresses or extends. This means a hatch may feel heavy at one point in its travel and overly eager at another. Springs also do not provide the damping of a gas strut, so a lid can snap open or close unless separate dampers, stops or restraints are added.

For guarded machinery or enclosed mechanisms, springs should be shielded where practical. A broken or dislodged spring can release stored energy quickly, and exposed coils can create pinch points.

Torsion springs for hinges and compact lids

Torsion springs work by twisting around a shaft or hinge line. They are commonly used on small access panels, cabinet doors, flip-up seats and compact covers where there is no room for a strut alongside the opening.

A torsion spring can make an unobtrusive installation, particularly when designed into the hinge assembly. It is well suited to lightweight lids with a predictable opening arc. Unlike a gas strut, it does not require ball studs, brackets or a long stroke path.

Its useful support range is narrower than many people expect. The torque changes as the lid rotates, and the spring must be matched carefully to the lid weight and centre of gravity. If a toolbox lid carries variable loads, such as mounted equipment or removable trays, a torsion spring may no longer provide the right assistance.

Counterweights and cable systems

A counterweight offsets load by using mass, usually connected through cable, chain or pulleys. On large vertical doors, heavy machine guards and industrial hatches, this can provide consistent assistance over a long travel distance.

The benefit is predictable balancing. With the right pulley arrangement, a counterweight can make a substantial door feel almost neutral through most of its movement. It does not lose force due to gas leakage over time, and it can be designed for very heavy loads.

The trade-off is space and guarding. The counterweight needs a travel path, cables require inspection, and all moving components must be protected from people, tools and debris. In mobile applications such as utes, trailers and caravans, added mass and movement under vibration usually make counterweights less practical than gas struts.

Electric linear actuators

Electric actuators are the logical choice when the lid, hatch or panel must open at the push of a button. They are used in powered canopies, agricultural equipment, industrial access doors, adjustable seating and specialised vehicle fit-outs.

An actuator provides controlled powered motion and can be paired with switches, remote controls, limit switches and interlocks. It can hold position without relying on an operator, depending on the actuator design. This is useful where a heavy hatch must be operated frequently or safely from a distance.

Power brings additional requirements. You need an appropriate electrical supply, wiring protection, weatherproof connectors and a plan for manual operation if power is unavailable. Actuators are generally slower than a manually assisted lid, and their duty cycle matters. A unit intended for occasional canopy use may overheat or wear prematurely on production machinery that cycles repeatedly throughout the day.

Do not assume an actuator can safely hold a load just because it can lift it. Check its rated dynamic load, static holding capacity, stroke, retracted length, ingress protection and mounting arrangement. Side loading is a common cause of premature actuator failure.

Hydraulic cylinders for high-force equipment

Hydraulic cylinders suit applications where forces are beyond the practical range of gas struts or electric actuators. Tipping bodies, heavy agricultural implements, mining equipment and industrial plant often use hydraulic power because it can move substantial loads with controlled force.

They are not a straightforward substitute for a gas strut. A hydraulic cylinder needs a pump, hoses, valves, fluid reservoir and properly rated fittings. Leaks, hose damage and pressure hazards must be managed. For a simple caravan locker lid or vehicle tool box, the additional cost and complexity rarely make sense.

Where high force and controlled movement are essential, hydraulics can be the correct engineering solution. The system should be designed with load-holding valves or mechanical locks where a raised component could endanger people if pressure is lost.

Locking stays, prop rods and friction hinges

Sometimes the real requirement is not lift assistance but safe open positioning. A locking stay, prop rod or friction hinge can hold a lid open without adding much force to the opening action.

These options work well for light cabinet doors, small lockers and access covers that are opened infrequently. They are compact, inexpensive and generally easy to inspect. A positive locking stay is also useful as a secondary safety support on larger access panels.

They are less suitable where the operator needs to lift a heavy panel one-handed, where wind can catch an open hatch, or where controlled closing is needed. A prop rod can be forgotten, bent or dislodged. Friction hinges can loosen over time, particularly in high-vibration vehicle and marine environments.

Choosing between gas spring alternatives

The right mechanism is determined by more than the overall weight of the lid. A 25 kg hatch with its centre of gravity close to the hinge can need less support than a 10 kg hatch with weight concentrated at the outer edge. Mounting points, opening angle and the direction of travel all affect the force required.

For any replacement or new design, record these details before ordering or fabricating hardware:

• component weight and any likely added load
• hinge type, pivot position and required opening angle
• available mounting space and the full travel path
• whether controlled opening, damping or powered movement is required
• operating environment, including dust, salt spray, heat and vibration
• safety needs if the lid, guard or hatch is above people.

It is also worth considering how the component behaves at both ends of travel. A system that holds a hatch well when fully open may still be difficult to start lifting from closed. Conversely, a setup that gives strong initial lift can place excessive force on hinges and brackets near full extension.

Do not overlook a correctly specified strut

Many applications that appear to need an alternative simply have the wrong gas strut fitted. Force is often selected by guesswork, while extended length, compressed length and bracket geometry are ignored. The result can be a lid that twists, mounts that fatigue or a strut that bottoms out before the hatch reaches its stop.

For vehicle canopies, caravan doors, marine lockers, machinery covers and toolboxes, a matched gas strut usually delivers the best balance of compact size, controlled movement and straightforward service. Custom force ratings and end fittings can often address unusual loads without redesigning the whole opening system.

When the job calls for a different approach, choose the mechanism around the hazard and duty cycle, not just the initial purchase price. A clear set of measurements and application details gives a strut specialist or engineer the information needed to recommend hardware that will keep working when the lid is heavy, the site is dusty and downtime is not an option.

A gas spring can still have plenty of lifting force left when corrosion starts to make it unreliable. A pitted rod damages the seal every time the strut cycles, while corrosion around brackets, end fittings or the cylinder can turn a routine lift into a safety issue. To prevent gas spring corrosion, treat the strut as a working component, not a fit-and-forget part – especially on utes, trailers, caravans, boats, agricultural gear and outdoor machinery.

The right approach depends on where the strut works. A toolbox exposed to road spray needs different protection from a cabinet strut inside a clean workshop. The same principles apply, however: select suitable materials, mount the strut correctly, keep contaminants off the rod and inspect it before surface damage reaches the seal.

Why gas springs corrode

Most gas springs use a steel cylinder with a treated or coated finish and a polished piston rod. These surfaces are designed for normal service, but moisture, salt, fertiliser, cleaning chemicals, metal dust and trapped dirt can break down that protection.

The piston rod deserves particular attention. It passes through the main seal on every stroke. If the chrome or protective surface is scratched, rust can form in the damaged area. Even small pits act like an abrasive edge, wearing the seal and allowing gas pressure to escape. The first symptom is often a lid, hatch or access panel that no longer stays open.

Corrosion is not limited to the rod. End fittings, ball studs, mounting brackets and fasteners can seize or lose strength. On dissimilar metals, such as a steel fitting mounted directly to aluminium in a wet environment, galvanic corrosion may also develop. Marine fitments and equipment operating near the coast are particularly exposed.

Select the right strut for the environment

Standard gas springs are suitable for many enclosed, low-exposure applications. For equipment regularly exposed to rain, mud, salt air, wash-downs or chemical residue, material choice should be part of the original specification rather than an afterthought.

Stainless steel gas springs are generally the better option for marine, food-processing, coastal, wash-down and corrosive industrial environments. They offer stronger resistance across the cylinder, rod and fittings, although not every stainless grade performs equally in every chemical or saltwater condition. For high-salt applications, confirm the strut material, end fittings and mounting hardware as a complete assembly.

Coated steel units can be a sound, cost-effective choice where exposure is occasional and routine cleaning is realistic. The trade-off is that coating damage needs attention early. A scratched or chipped cylinder on a trailer, farm implement or machinery enclosure can become a corrosion point if it remains wet or packed with grime.

Do not select a strut on force alone. When replacing or specifying a unit, confirm the extended and compressed lengths, stroke, force rating, end fitting type, mounting position and operating environment. A correctly rated strut with unsuitable materials will still have a short service life in harsh conditions.

Mounting practices that help prevent gas spring corrosion

For most conventional gas springs, mounting with the piston rod pointing down when the unit is closed helps keep internal seal lubrication where it is needed. This reduces seal wear and can improve service life. There are exceptions, including certain lockable, damped or application-specific struts, so follow the recommended orientation for the particular unit.

Mounting geometry also matters. A strut that is forced to side-load, twist or run out of line puts extra load on the rod and seal. Over time, this can score the rod surface or wear the seal unevenly. Check that brackets are aligned, ball joints can articulate freely and the lid or panel is not flexing through its travel.

Avoid locations where a closed strut becomes a collection point for water, mud, leaf litter or fertiliser. If the application cannot avoid exposure, provide drainage and make cleaning accessible. On a canopy, plant enclosure or trailer box, a small change to bracket position can stop water sitting against the cylinder or fittings.

Fasteners and brackets should match the environment as well. Corrosion-resistant ball studs and brackets are worthwhile where the strut is exposed, but consider the mounting surface too. Isolate incompatible metals where practical and replace damaged fasteners rather than reusing seized or heavily corroded hardware.

Clean the rod without damaging it

The best maintenance task is also the simplest: inspect and clean the exposed piston rod regularly. Wipe off dust, salt residue and grime with a soft, clean cloth. For heavier contamination, use water and a mild detergent, then dry the rod fully. This is especially useful after beach driving, launching a boat, travelling on treated roads or working around fertiliser and chemicals.

Do not attack the piston rod with abrasive paper, wire brushes or aggressive polishing compounds. These can damage the smooth finish the seal relies on. Avoid directing a high-pressure washer straight at the rod seal, end seals or cylinder joints. Pressure can force water and contaminants into places they would not normally reach.

Heavy grease is not a general answer. It can hold abrasive dust and grit against the rod, creating the very wear it is meant to prevent. Likewise, do not paint the rod, cover it in tape or apply an unapproved coating. Anything that changes the rod surface can harm seal performance. If a protective product is being considered for a specialised application, confirm that it is compatible with the strut seal and manufacturer recommendations.

A practical inspection routine

For fleet, workshop and plant equipment, inspect gas springs as part of scheduled maintenance. For privately owned caravans, trailers and vehicles, check them before longer trips and after sustained wet, coastal or off-road use. Look for the following:

• Rust spots, pitting, scratches or flaking finish on the piston rod or cylinder
• Dampness, oil residue or dirt build-up around the rod seal
• Loose, seized or corroded ball joints, brackets and fasteners
• A lid, hatch or panel that drops, lifts unevenly or needs help to stay open
• Rod bending, binding or contact with adjacent hardware during operation

A small surface mark on the outer cylinder may be manageable if cleaned and protected promptly. Pitting on the piston rod, a leaking seal or reduced holding force is different. Replacement is usually the sensible option because a damaged rod will continue to wear the seal and cannot be reliably restored in service.

Reduce exposure in harsh Australian conditions

Australian operating conditions can be hard on gas springs. Coastal salt, red dust, tropical humidity, farm chemicals and regular road spray each create their own maintenance demands. A strut on a rear canopy door may see dust and rain daily; one on a boat hatch may receive salt deposits after every outing.

Rinse salt and chemical residue off exposed assemblies promptly, using low-pressure fresh water where appropriate. Drying matters as much as rinsing. Moisture trapped behind brackets, under rubber boots or around end fittings has time to work on the metal long after the equipment is parked.

If a gas spring is fitted behind a guard, inspect the guard as well. Guards can reduce stone damage, but a poorly drained cover may trap moisture and dirt. The better design is one that shields the rod from direct spray while allowing the area to drain and be cleaned.

For machinery and plant applications, record strut replacements and failure locations. If the same position repeatedly develops corrosion, the issue may be the installation environment rather than the part itself. Changing to stainless construction, revising bracket placement or adding drainage may deliver a better result than repeatedly fitting the same standard strut.

Replace compromised struts before they become unsafe

Gas springs are pressurised components. Do not drill, crush, heat, puncture or attempt to recharge one. If corrosion has affected the rod, cylinder integrity or mounting points, support the lid or panel safely and replace the strut as a pair where two units share the load. A new strut beside a weak, older one can make the panel lift unevenly and overload the remaining unit.

Before ordering, measure the extended length from centre to centre of the end fittings, compressed length, stroke and fitting style. Note any printed force rating and the application details, including panel weight, mounting points and exposure to salt, chemicals or wash-down. This gives a strut specialist enough information to identify a direct replacement or advise on a more suitable corrosion-resistant option.

A clean rod, sound fittings and the right material specification cost far less than a failed hatch, damaged lid or unsafe access panel. Build gas spring checks into normal equipment care, and replace early when corrosion reaches a sealing or load-bearing surface.

A bonnet that will not stay open is more than an inconvenience. It creates a safety issue around batteries, radiators, belts and engine components, particularly when the vehicle is being serviced in a workshop, on site or in the driveway. When searching for the best bonnet supports Australia has available, the right answer is not simply the strongest gas strut. It is the support matched accurately to your bonnet weight, mounting geometry and intended use.

A correctly specified bonnet strut lifts smoothly, holds the bonnet securely at its designed opening angle and closes without excessive effort. One that is too weak can let the bonnet drop. One that is too strong can make closing difficult, load up hinges and brackets, or twist a lightweight bonnet over time.

What makes a bonnet support the right one?

Gas bonnet supports, often called gas struts or gas springs, use pressurised gas and oil damping to control lifting and closing. They are commonly fitted to utes, four-wheel drives, passenger vehicles, machinery and custom engine covers. While many look similar, their performance depends on several specifications working together.

The first is force, measured in Newtons (N). This is the pushing force generated by the strut. A bonnet may need anything from a relatively light-force unit to a substantially stronger strut, depending on its size, construction, accessories and mounting position. Aluminium and fibreglass bonnets can behave very differently from steel bonnets, and a bonnet with soundproofing, a scoop or added equipment may need a revised calculation.

Length matters just as much. Extended length determines the open position, while compressed length determines whether the strut can close without bottoming out. A strut that is only slightly too long or too short may appear close enough on the bench but fail to operate correctly once mounted.

End fittings and brackets complete the fitment. Ball sockets are common, but eyelets, clevises, pin mounts and fixed threaded ends are also used. The fitting must suit the existing brackets, provide sufficient articulation through the bonnet travel and avoid contact with surrounding components.

Best bonnet supports in Australia are matched, not guessed

Replacing an existing strut is usually straightforward when the original part number and specifications are still readable. The stamped marking may show an extended length, force rating and manufacturer reference. Use it as a starting point, but confirm the measurements before ordering, especially if the vehicle has been modified or the brackets have been changed.

If there is no readable part number, measure the strut from centre of fitting to centre of fitting, not from the end of the tube. Take both measurements with the strut fully extended and fully compressed where possible. Record the diameter of the rod and body, the style of end fitting, and the force rating if known.

For a custom bonnet setup, measurements alone are not enough. The bonnet weight, hinge location, desired opening angle and lower and upper mounting positions all affect the required force. A strut mounted closer to the bonnet hinge has less leverage and generally needs more force than one mounted further out. This is why copying a strut from another vehicle can produce a poor result even when the bonnet appears similar.

To get an accurate replacement or quote, provide these details:

• vehicle make, model, year and body style, or machinery make and model;
• existing strut part number and force rating, if available;
• extended and compressed centre-to-centre lengths;
• photos or a clear description of both end fittings and mounting brackets; and
• whether the bonnet has accessories, modifications or non-standard hinges.

Those details allow a strut specialist to confirm whether an off-the-shelf replacement is suitable or whether a custom force and fitting combination is required.

Do not choose force by how hard the old strut feels

A worn gas strut is not a reliable reference point. Gas pressure reduces over time, seals wear and performance can deteriorate more noticeably in cold weather. If a bonnet has become difficult to hold up, the original strut may now be producing far less than its marked force.

Equally, fitting a heavier-rated strut just to make the bonnet rise faster is rarely a good fix. Excessive force may cause the bonnet to spring open sharply, strain mounting brackets or make it awkward for a shorter operator to pull down. On a vehicle with two struts, uneven force between the left and right sides can also place unnecessary load on hinges and create uneven bonnet movement.

Replace paired bonnet struts together where practical. Even if only one has visibly failed, the other will have experienced the same age, heat cycles and operating conditions. A matched pair provides balanced support and more predictable operation.

Check the mounting layout before fitting new supports

Bonnet support failure is sometimes blamed on the gas strut when the real issue is a worn ball stud, loose bracket, bent mounting tab or damaged bonnet hinge. Inspect the mounting points before installing replacement struts. A ball stud should be firmly secured, and the socket should click on positively without excessive play.

Check clearance through the whole opening and closing movement. The strut body, rod and fittings must not rub on the guard, wiring, washer bottle, insulation or engine components. Pay particular attention to aftermarket bonnet conversions and custom builds, where a small change to bracket placement can have a large effect on movement and force requirements.

Where design allows, install the strut with the rod pointing down when the bonnet is closed. This helps keep the internal seal lubricated and can support longer service life. It is not possible in every installation, so existing engineered mounting geometry should take priority.

Installation is simple, but support the bonnet first

Most replacement bonnet struts use retaining clips at the socket ends. These clips usually only need to be eased back slightly so the socket can be removed from the ball stud. Do not fully remove and lose the clip unless the fitting design requires it.

Always support the bonnet independently before removing either strut. Use a suitable prop, have another person hold it securely, or use workshop lifting equipment. Do not rely on one tired strut to hold the load while the other is being changed.

Fit one strut at a time if the layout permits. Press each socket onto its ball stud until it seats fully, then check that the retaining clip is engaged. Open and close the bonnet slowly several times, watching for interference and confirming the safety catch and primary latch still operate normally. Never drill new bonnet or body mounting holes without confirming structural suitability and clearance on both sides of the panel.

When a custom bonnet strut is the better option

Custom gas struts are often the sensible choice for modified four-wheel drives, engine conversions, race vehicles, machinery covers and older vehicles where original parts are unavailable. They are also useful where an existing bonnet opens too low, requires a different bracket arrangement or carries additional weight.

The trade-off is that custom work needs better information upfront. A supplier may need photos, dimensions, bonnet weight and measurements at closed and open positions to calculate the correct force. That process prevents the common mistake of buying a generic strut, fitting it successfully for a day, then finding it will not close or cannot safely hold the bonnet in warm conditions.

Gas Struts can assist with standard replacement units as well as application-specific strut and fitting combinations, which is useful when a catalogue match is not enough. For workshop fleets and maintenance teams, recording the final length, force and fitting specification also makes future replacements faster and reduces downtime.

Expect performance suited to Australian working conditions

Bonnet struts operate near engine heat, road grime, vibration and changing temperatures. In regional work, agricultural and mining applications, dust and repeated daily cycles add further wear. Quality construction, sound seals and correctly matched fittings matter more than a low initial price when the bonnet is opened constantly or access is safety-critical.

Inspect bonnet supports during regular servicing. Look for oil around the rod seal, corrosion on the rod, damaged sockets, loose brackets and a bonnet that no longer reaches or holds its normal open position. Do not paint the rod, clamp it with grips or lubricate it with heavy grease. Damage to the polished rod can quickly compromise the seal.

The best choice is the one that fits the vehicle, controls the load and remains dependable over repeated use. Start with the original specifications where available, measure carefully where they are not, and seek technical advice before substituting a different force or length. A correctly selected bonnet support is a small component that makes routine engine access safer and far less frustrating.

A bonnet that will not stay open is more than an inconvenience. It creates a safety issue around batteries, radiators, belts and engine components, particularly when the vehicle is being serviced in a workshop, on site or in the driveway. When searching for the best bonnet supports Australia has available, the right answer is not simply the strongest gas strut. It is the support matched accurately to your bonnet weight, mounting geometry and intended use.

A correctly specified bonnet strut lifts smoothly, holds the bonnet securely at its designed opening angle and closes without excessive effort. One that is too weak can let the bonnet drop. One that is too strong can make closing difficult, load up hinges and brackets, or twist a lightweight bonnet over time.

What makes a bonnet support the right one?

Gas bonnet supports, often called gas struts or gas springs, use pressurised gas and oil damping to control lifting and closing. They are commonly fitted to utes, four-wheel drives, passenger vehicles, machinery and custom engine covers. While many look similar, their performance depends on several specifications working together.

The first is force, measured in Newtons (N). This is the pushing force generated by the strut. A bonnet may need anything from a relatively light-force unit to a substantially stronger strut, depending on its size, construction, accessories and mounting position. Aluminium and fibreglass bonnets can behave very differently from steel bonnets, and a bonnet with soundproofing, a scoop or added equipment may need a revised calculation.

Length matters just as much. Extended length determines the open position, while compressed length determines whether the strut can close without bottoming out. A strut that is only slightly too long or too short may appear close enough on the bench but fail to operate correctly once mounted.

End fittings and brackets complete the fitment. Ball sockets are common, but eyelets, clevises, pin mounts and fixed threaded ends are also used. The fitting must suit the existing brackets, provide sufficient articulation through the bonnet travel and avoid contact with surrounding components.

Best bonnet supports in Australia are matched, not guessed

Replacing an existing strut is usually straightforward when the original part number and specifications are still readable. The stamped marking may show an extended length, force rating and manufacturer reference. Use it as a starting point, but confirm the measurements before ordering, especially if the vehicle has been modified or the brackets have been changed.

If there is no readable part number, measure the strut from centre of fitting to centre of fitting, not from the end of the tube. Take both measurements with the strut fully extended and fully compressed where possible. Record the diameter of the rod and body, the style of end fitting, and the force rating if known.

For a custom bonnet setup, measurements alone are not enough. The bonnet weight, hinge location, desired opening angle and lower and upper mounting positions all affect the required force. A strut mounted closer to the bonnet hinge has less leverage and generally needs more force than one mounted further out. This is why copying a strut from another vehicle can produce a poor result even when the bonnet appears similar.

To get an accurate replacement or quote, provide these details:

• vehicle make, model, year and body style, or machinery make and model;
• existing strut part number and force rating, if available;
• extended and compressed centre-to-centre lengths;
• photos or a clear description of both end fittings and mounting brackets; and
• whether the bonnet has accessories, modifications or non-standard hinges.

Those details allow a strut specialist to confirm whether an off-the-shelf replacement is suitable or whether a custom force and fitting combination is required.

Do not choose force by how hard the old strut feels

A worn gas strut is not a reliable reference point. Gas pressure reduces over time, seals wear and performance can deteriorate more noticeably in cold weather. If a bonnet has become difficult to hold up, the original strut may now be producing far less than its marked force.

Equally, fitting a heavier-rated strut just to make the bonnet rise faster is rarely a good fix. Excessive force may cause the bonnet to spring open sharply, strain mounting brackets or make it awkward for a shorter operator to pull down. On a vehicle with two struts, uneven force between the left and right sides can also place unnecessary load on hinges and create uneven bonnet movement.

Replace paired bonnet struts together where practical. Even if only one has visibly failed, the other will have experienced the same age, heat cycles and operating conditions. A matched pair provides balanced support and more predictable operation.

Check the mounting layout before fitting new supports

Bonnet support failure is sometimes blamed on the gas strut when the real issue is a worn ball stud, loose bracket, bent mounting tab or damaged bonnet hinge. Inspect the mounting points before installing replacement struts. A ball stud should be firmly secured, and the socket should click on positively without excessive play.

Check clearance through the whole opening and closing movement. The strut body, rod and fittings must not rub on the guard, wiring, washer bottle, insulation or engine components. Pay particular attention to aftermarket bonnet conversions and custom builds, where a small change to bracket placement can have a large effect on movement and force requirements.

Where design allows, install the strut with the rod pointing down when the bonnet is closed. This helps keep the internal seal lubricated and can support longer service life. It is not possible in every installation, so existing engineered mounting geometry should take priority.

Installation is simple, but support the bonnet first

Most replacement bonnet struts use retaining clips at the socket ends. These clips usually only need to be eased back slightly so the socket can be removed from the ball stud. Do not fully remove and lose the clip unless the fitting design requires it.

Always support the bonnet independently before removing either strut. Use a suitable prop, have another person hold it securely, or use workshop lifting equipment. Do not rely on one tired strut to hold the load while the other is being changed.

Fit one strut at a time if the layout permits. Press each socket onto its ball stud until it seats fully, then check that the retaining clip is engaged. Open and close the bonnet slowly several times, watching for interference and confirming the safety catch and primary latch still operate normally. Never drill new bonnet or body mounting holes without confirming structural suitability and clearance on both sides of the panel.

When a custom bonnet strut is the better option

Custom gas struts are often the sensible choice for modified four-wheel drives, engine conversions, race vehicles, machinery covers and older vehicles where original parts are unavailable. They are also useful where an existing bonnet opens too low, requires a different bracket arrangement or carries additional weight.

The trade-off is that custom work needs better information upfront. A supplier may need photos, dimensions, bonnet weight and measurements at closed and open positions to calculate the correct force. That process prevents the common mistake of buying a generic strut, fitting it successfully for a day, then finding it will not close or cannot safely hold the bonnet in warm conditions.

Gas Struts can assist with standard replacement units as well as application-specific strut and fitting combinations, which is useful when a catalogue match is not enough. For workshop fleets and maintenance teams, recording the final length, force and fitting specification also makes future replacements faster and reduces downtime.

Expect performance suited to Australian working conditions

Bonnet struts operate near engine heat, road grime, vibration and changing temperatures. In regional work, agricultural and mining applications, dust and repeated daily cycles add further wear. Quality construction, sound seals and correctly matched fittings matter more than a low initial price when the bonnet is opened constantly or access is safety-critical.

Inspect bonnet supports during regular servicing. Look for oil around the rod seal, corrosion on the rod, damaged sockets, loose brackets and a bonnet that no longer reaches or holds its normal open position. Do not paint the rod, clamp it with grips or lubricate it with heavy grease. Damage to the polished rod can quickly compromise the seal.

The best choice is the one that fits the vehicle, controls the load and remains dependable over repeated use. Start with the original specifications where available, measure carefully where they are not, and seek technical advice before substituting a different force or length. A correctly selected bonnet support is a small component that makes routine engine access safer and far less frustrating.

A solar panel mounted flat to a caravan roof, canopy or equipment enclosure is protected, but it can be hard to clean, inspect or angle towards the sun. A correctly designed solar panel lift strut example shows how gas struts can make that panel easier to raise without creating a lid that is too heavy to close, too difficult to control or unsafe in wind.

The key point is simple: a gas strut is not selected from panel weight alone. The mounting position, panel length, hinge location, opening angle and the weight of the frame all affect the force required. Getting one of those details wrong can leave the panel lifting too aggressively, sagging halfway open or placing unnecessary stress on hinges and brackets.

A practical solar panel lift strut example

Consider a common canopy installation. A framed solar panel is mounted to a hinged aluminium frame on the roof of a ute canopy. The panel assembly weighs 18 kg, measures 1,600 mm long from hinge to outer edge, and needs to open to approximately 45 degrees for cleaning, maintenance and improved solar exposure when parked.

The hinge runs along the 1,600 mm side of the frame. Because the panel’s centre of gravity sits roughly halfway from the hinge, its effective load acts about 400 mm from the hinge on an 800 mm-deep frame. The gas strut is mounted around 250 mm from the hinge on the fixed canopy structure and 550 mm from the hinge on the moving frame. These dimensions determine the strut’s leverage through the lift.

In this arrangement, one strut is rarely the right answer. A pair of matched gas struts – one on each side – shares the load, keeps the panel frame from twisting and reduces concentrated stress at the mounting points. Depending on the exact bracket geometry, a starting force range may be around 250 N to 350 N per strut. That is a guide only, not a final specification.

A strut at the lower end of that range may support the panel neatly once it is open but require a firm initial lift. A higher-force strut may provide better opening assistance, yet can make the panel harder to latch shut and can force it open when released. The correct choice comes from checking the force at both closed and open positions, not picking the biggest available strut.

Why panel weight is only the starting point

An 18 kg panel assembly has a downward force of roughly 177 N, but that figure cannot be matched directly to a 177 N gas strut. Gas struts work through an angle and a mounting distance. Their usable lifting force changes as the panel moves.

When the panel is closed, the strut often has less mechanical advantage. This is usually where the greatest force is needed to start the lift. As the panel opens, the strut angle and leverage improve, while the panel’s centre of gravity moves relative to the hinge. A layout that feels right near full extension may still be underpowered at the first 100 mm of lift.

The reverse problem is common too. If a high-force strut is fitted close to the hinge, it may generate excessive force when closed. The frame can bow, brackets can loosen, and a user may need to pull the panel down against the strut pressure. Solar hardware is often lightweight aluminium, so bracket strength deserves the same attention as the strut force.

Measurements needed to specify a lift strut

For a reliable quote or replacement, provide the panel assembly weight rather than the bare panel weight. Include the frame, rails, hinges, latch hardware, wiring protection and any tilting brackets. A small difference in weight can matter when the strut is working close to its limit.

You will also need the fully open and fully closed measurements between the two strut mounting centres. Measure centre-to-centre from the ball stud, eyelet or clevis pin at each end. The closed length must be longer than the compressed length of the chosen strut, while the open length must remain within its available stroke.

Mounting positions matter just as much. Record the distance from the hinge pivot to each mounting centre: one on the fixed structure and one on the moving panel frame. A clear side-on photo or simple sketch with dimensions is often enough to assess the geometry accurately.

Also specify the intended open angle. A panel lifted to 25 degrees needs a different layout from one opening to 60 degrees. If the frame must clear an awning, roof rack, canopy door or rooftop equipment, include that clearance in the design from the outset.

Selecting the right strut configuration

Use two struts for wide panel frames

A single central strut can work on a narrow access panel, but wide solar frames are better supported by two struts. Paired struts distribute force across the frame and help it rise evenly. This is particularly relevant on canopies, caravans, service bodies and marine installations where vibration and rough-road movement can work on fittings over time.

The struts need to be the same model and force rating. Mixing an old strut with a new one, or fitting two different forces, can make the panel rack as it opens. Replace them as a matched pair when both sides share the lifting duty.

Choose fittings for the operating environment

Ball joints are widely used because they tolerate movement through the opening arc and allow quick removal where servicing is needed. Eyelets and clevis fittings can suit installations with purpose-built brackets or limited side clearance. What matters is that the fitting can articulate freely without binding at either end of travel.

For outdoor solar applications, use corrosion-resistant components suited to exposed conditions. A panel on a caravan or canopy sees rain, dust, road spray, heat and vibration. Stainless hardware may be appropriate in coastal or marine environments, but the full mounting arrangement still needs to be compatible with the frame material to manage corrosion risk.

Do not rely on the struts in strong wind

Gas struts support the panel, but they are not a wind lock. A raised panel can act like a sail, especially on an exposed campsite, worksite or boat berth. Use positive latches, support stays or locking hardware where the panel may be left open. If it is only raised for cleaning or inspection, lower it before conditions change.

Installation details that prevent failures

Mount the cylinder end of the gas strut uppermost where practical, with the rod pointing down when the panel is closed or in its normal parked position. This helps keep the internal seal lubricated. Avoid mounting the strut where it can be used as a physical stop at full extension or full compression. The hinges, stops and brackets should control the travel, not the strut itself.

Check that the strut does not foul solar cables, gland fittings, sharp frame edges or roof accessories throughout the whole arc. Allow room to remove the strut for service. On aluminium frames, use adequate backing plates or reinforced bracket sections rather than fixing a high-load bracket into thin sheet alone.

Before final tightening, open and close the panel slowly several times. Look for side loading, bracket flex, binding ball joints and excessive closing force. If the panel lifts strongly at the beginning but loses support near the desired angle, changing the mounting geometry may solve the issue better than simply increasing the force rating.

When a custom calculation is worthwhile

A standard gas strut can be suitable for a straightforward panel frame, but custom advice is worthwhile when the setup includes large panels, dual-panel arrays, unusual hinge locations, heavy protective covers or a required locking position. The same applies where a panel is mounted on mining, agricultural, marine or mobile service equipment subject to constant vibration.

Provide the panel assembly weight, open and closed centre measurements, hinge-to-mount distances, required opening angle, photos and preferred fittings. With those details, a strut specialist can assess force, stroke, extended length and mounting geometry as a complete system rather than treating the strut as an isolated part.

A solar panel lift should feel controlled in the hand: manageable to start, supported at the working angle and secure when closed. Taking the time to measure the full movement will protect the panel, the roof structure and the person operating it.

A failed strut on a toolbox lid, boat hatch or machinery guard is more than an inconvenience. It can stop access, create a safety risk and expose equipment to damage. When comparing stainless gas struts vs steel, the right choice is usually determined by the environment around the strut, not simply by the initial purchase price.

Standard steel gas struts are a practical, cost-effective option for many dry applications. Stainless steel struts cost more, but can deliver far better service life where salt, moisture, wash-down chemicals or corrosive dust are part of the job. The key is to specify the material, force and fittings as one system.

Stainless gas struts vs steel: the main difference

The central difference is corrosion resistance. A standard steel gas strut commonly has a painted, powder-coated or plated cylinder, with a hardened and chrome-plated rod. This construction suits vehicle boots, canopies, cabinets, indoor machinery, trailers and equipment that is generally kept dry.

A stainless gas strut uses stainless steel for corrosion-prone external components, commonly the cylinder and end fittings. Depending on the product specification, the rod may also be stainless steel. These struts are intended for harsh service where coated steel can eventually chip, wear or rust.

That distinction matters because gas struts operate on a sliding rod seal. Once corrosion, pitting or surface damage develops on the rod, the seal can wear quickly. Oil loss follows, gas pressure drops and the strut no longer provides its rated support force.

Stainless is not automatically necessary for every outdoor application. A steel strut fitted under a covered ute canopy may last well when it is protected from constant rain and road spray. The same strut on a saltwater boat hatch, exposed caravan storage door or coastal plant enclosure faces a very different workload.

When steel gas struts are the sensible choice

Steel gas struts remain the standard choice for a reason. They are widely available, economical and well suited to applications where exposure is limited and routine maintenance is realistic. For workshops, enclosed toolboxes, indoor cabinets, machinery covers and many automotive replacements, a quality steel strut can provide dependable service.

Choose steel when the installation is mostly dry, corrosion is not the primary failure risk and replacement access is straightforward. They are also a sensible option where a large number of struts are used on equipment that is regularly inspected and maintained.

For a vehicle bonnet or boot, the correct extended length, compressed length, mounting ends and force rating will usually matter more than whether the body is stainless. A poorly matched stainless strut is still a poor fit. It may overextend the panel, fail to hold it open or place excess load on hinges and brackets.

Steel is also often appropriate for agricultural or industrial equipment that works in dusty conditions but is stored under cover. Dust can damage any strut rod if it is allowed to build up, so a stainless body does not remove the need for cleaning and inspection.

Where stainless steel earns its higher cost

Stainless gas struts are most valuable when corrosion is likely to shorten the life of a conventional unit. Marine hatches, bait boards, livewell lids, offshore equipment, food-processing machinery, wash-down areas and coastal installations are common examples.

On boats and near-shore equipment, salt deposits can sit on rods, fittings and brackets for extended periods. Coastal air alone can be enough to attack standard finishes, particularly around threaded ends, ball studs and mounting brackets. Stainless construction reduces this risk, provided the grade is suitable and the full installation is considered.

Caravans, campers, horse floats and trailers can also benefit from stainless struts when they are frequently exposed to rain, mud, road spray or beach environments. For a front storage hatch that is opened daily on touring trips, the additional upfront cost can be justified by fewer premature replacements and less risk of a lid dropping unexpectedly.

Wash-down environments deserve particular care. Food production, medical, chemical and processing facilities may use water, detergents or cleaning agents that are far harder on metal than ordinary rainwater. In these applications, ask for material details rather than assuming that any product described as stainless will suit the chemical exposure.

Stainless grades and fittings matter as much as the strut body

Not all stainless steel performs the same way. Grade 304 stainless offers useful corrosion resistance for many general applications. Grade 316 stainless has better resistance to chlorides, making it the preferred choice for marine and highly corrosive coastal conditions.

The practical point is simple: do not specify a 316 stainless strut and then fit it with mild-steel brackets, ordinary ball studs or zinc-plated fasteners in a saltwater environment. Those parts may corrode first, making removal difficult or compromising the mounting point.

Where dissimilar metals meet, galvanic corrosion can also become a concern. This occurs when different metals are electrically connected in the presence of moisture, with one material corroding faster than it otherwise would. aluminium hatches, stainless fittings and marine mounting hardware need to be selected with the complete assembly in mind. Appropriate isolators, fasteners and regular cleaning can help control the risk.

Before ordering, confirm whether stainless refers to the tube, rod, end fittings or the whole assembly. Product descriptions vary across suppliers, and the difference has a direct effect on expected service life.

Do stainless struts lift more than steel struts?

No. Lift capacity is determined by the gas pressure inside the strut, expressed in Newtons, along with the mounting geometry and the weight distribution of the lid, door or panel. Stainless and steel struts are available in a range of force ratings, so material choice does not determine lifting strength.

A 500N strut is designed to exert approximately 500 Newtons of extension force under specified conditions. It does not mean it will safely lift every 50 kg lid. The actual requirement depends on the lid weight, its centre of gravity, hinge position, angle of opening and the distance between mounting points.

This is why replacing a weak strut with a higher-force unit can create another problem. Too much force can make a hatch hard to close, bend light panels, overload hinges or cause a lid to spring open aggressively. Select the correct force first, then choose steel or stainless construction for the environment.

How to choose the right strut for the job

Start by assessing what the strut is exposed to over its working life. Rain once a month is different from daily wash-down. Occasional coastal travel is different from permanent marine use. Also consider access: a strut mounted inside a simple cabinet can be replaced quickly, while one fitted behind a boat hatch lining or on production equipment may be costly to change.

Then record the existing strut specifications. Measure the extended length from the centre of one mounting point to the centre of the other. Measure the compressed length in the same way, identify the end fittings and note the force rating printed on the cylinder, such as 350N or 700N. If the original strut has no readable label, the lid dimensions, weight, hinge location and mounting positions are needed to calculate a suitable replacement.

Check the installation direction as well. In most applications, gas struts should be fitted with the rod facing down when the lid is closed. This keeps internal lubrication at the seal and supports longer service life. Some specialised applications differ, so follow the strut specification where relevant.

Finally, look at the brackets and fixings. A high-quality strut cannot compensate for loose rivets, fatigued sheet metal, corroded ball studs or a mounting point that has moved out of alignment. Repair the mounting issue before fitting replacements.

Service life depends on maintenance too

Even stainless struts need basic care. Wipe salt, grime and chemical residue from the rod with a clean cloth. Do not paint the rod, apply heavy grease to it or use abrasive cleaners that can damage the surface. Check that the end fittings articulate freely and that the strut is not being forced sideways through its travel.

For fleet, marine and industrial maintenance teams, replacing struts before total failure can avoid downtime and injuries. A lid that is slowing down, sagging in cold weather, leaking oil or showing rod corrosion should be inspected promptly rather than propped open with timber or handled by two people.

If the application works in salt, water, chemicals or constant outdoor exposure, stainless is usually the better long-term decision. For protected, dry and accessible equipment, a correctly specified steel strut remains a reliable and economical solution. The best result comes from matching the strut material to the environment and matching every measurement to the job.

A failed gas strut on a tractor bonnet, seed drill cover or field service box is more than an inconvenience. It can stop inspections, slow repairs and leave a heavy panel unsafe to handle. Agricultural struts need to cope with dust, vibration, weather and repeated use, while holding the panel at a practical working height.

The right replacement is not simply the one that looks similar. Extended length, compressed length, force rating and end fittings must all suit the application. Get one of these details wrong and the strut may not lift the load, may overextend the hinge, or may place unnecessary strain on mounting brackets.

Where agricultural gas struts are used

Gas struts are fitted across farm machinery wherever a lid, cover, hatch or access panel needs controlled lifting and support. Common applications include tractor and harvester bonnets, engine covers, service doors, battery boxes, grain handling equipment, spray rigs, augers, balers, livestock trailers and ute-mounted toolboxes.

They are also useful on fabricated equipment. A machinery builder may require struts for weatherproof enclosures, hydraulic service compartments or control-box lids. In these cases, a standard off-the-shelf strut can be suitable, but custom agricultural struts are often the better option where mounting points, opening angles or panel weights are specific to the build.

The operating environment matters. A strut that works well on a light cabinet door may not last on machinery that spends its days in corrugated paddocks, receives regular wash-downs and is exposed to heat, mud and fertiliser residue. Agricultural applications call for correctly specified components and sound mounting hardware, not a close enough substitute.

Start with the specifications, not the machine model

Machine make and model can help identify an original part, particularly where an OEM number is available. However, farm equipment is frequently modified, repaired or fitted with replacement panels over its working life. Measuring the existing strut remains the most reliable starting point.

For a replacement, record the extended length from the centre of one mounting point to the centre of the other when the strut is fully open. Measure the compressed length in the same way, then note the stroke, which is the difference between those two measurements. Check the force rating stamped on the body, usually expressed in Newtons, such as 400N, 600N or 900N.

Also identify the fittings at each end. Ball sockets, eyelets, clevis fittings and threaded ends are all common, and the thread size or ball-stud diameter can vary. A strut with the correct force but unsuitable fittings is not a correct replacement.

When supplying details for an agricultural strut, provide:

• extended length and compressed length, measured centre to centre
• force rating in Newtons, if marked on the existing strut
• end fitting type, thread size and mounting orientation
• a description or photo of the equipment and panel being supported

These details allow a specialist to check whether a direct replacement is appropriate or whether a different force, fitting or mounting position is needed.

Choosing the right force rating

Force is the point most likely to cause trouble. A weak strut may lift the panel initially but sag in cool weather, fail to hold it open or struggle once dust and accessories add weight. An overpowered strut can be just as problematic. It can make closing difficult, bend light panels, stress hinges and force the lid open too aggressively.

The correct rating depends on more than total panel weight. Mounting geometry has a major effect. A strut mounted close to the hinge has less leverage and generally needs more force than one mounted further along the panel. The opening angle also matters. A bonnet that needs to hold at 70 degrees may require a different arrangement from a cover that opens to 110 degrees.

Temperature adds another variable. Gas struts commonly feel stronger in heat and softer in cold conditions. On equipment used through frosty starts and hot summer days, allow for the normal operating range rather than selecting a rating based on one workshop test. If the cover carries work lights, soundproofing, tool holders or added guards, include that extra weight in the assessment.

For wide or heavy panels, two struts are usually used to distribute the load and reduce twisting. Both struts should be replaced as a pair. Fitting one new high-force strut beside an older weakened unit can cause uneven lifting and accelerate wear in the remaining strut, hinges and brackets.

Check brackets and hinges before fitting new struts

A new gas strut cannot correct worn hinges, cracked welds or loose mounting brackets. Before installation, inspect the attachment points for elongation, corrosion and movement. On older farm machinery, a loose ball stud or fatigued bracket is common, especially on engine covers that are opened regularly for daily checks.

Make sure the panel aligns properly when closed. If a bonnet has shifted after a hinge repair or vibration damage, the original strut length may no longer suit its travel. Forcing a strut to reach a misaligned bracket can damage the seals or bend the rod.

Where possible, install the strut with the rod pointing down when the panel is closed. This position helps keep internal lubrication around the rod seal and can support service life. There are exceptions depending on the application and fitting design, so follow the original layout or seek advice if the mounting arrangement is being changed.

Signs a strut needs replacement

Most failed struts give warning before they stop working completely. Slow lifting, a panel that will not stay open and visible oil around the rod are obvious signs. So are popping end fittings, a bent rod, rust pitting or a cover that drops partway through its travel.

Do not rely on a gas strut as the only safety support while working beneath a raised bonnet, hopper cover or heavy access door. Use the machine’s mechanical prop, safety stay or an appropriate external support before placing hands or body parts in a risk area. A strut can lose pressure without warning, particularly if its seal has been damaged by dirt or impact.

If failure happens away from the shed, a temporary prop may get the job done safely enough to move the machine or complete an urgent repair. It is not a replacement strategy. Continued operation with an unsupported panel risks injury and can damage hinges, latches and covers.

When a custom strut is the practical answer

Replacement struts are straightforward when original markings, dimensions and fittings are available. The job changes when equipment is older, imported, modified or purpose-built. That is where a custom solution can avoid repeated trial and error.

A suitable design can account for panel weight, centre of gravity, mounting locations, preferred open position and available clearance when closed. It may use a different end fitting, adjusted force rating or revised bracket position to produce controlled movement. This is particularly useful for fabricated machinery enclosures, retrofitted toolboxes, spray units and agricultural trailers.

Gas Struts can help match a replacement from measurements or specify a strut arrangement for a new application. Clear photos and accurate dimensions reduce delays and make it easier to supply the right hardware with the strut.

Fit for the work, not just the first lift

Agricultural equipment earns its keep in conditions that expose weak components quickly. A correctly matched gas strut should lift without launching the panel, hold it securely at the required position and close without excessive force. It should also suit the fittings and brackets already carrying the load.

Before ordering, take the extra few minutes to measure both lengths, confirm the Newton rating and inspect every mounting point. That small check is usually the difference between a field-ready repair and another part that has to be replaced before the season is out.

A bonnet that will not stay up is more than an annoyance at the servo or in the workshop. It can interrupt servicing, damage panels and create a genuine safety risk. Correct bonnet support installation gives the bonnet controlled lift, secure open support and enough clearance for hinges, wipers and under-bonnet components.

Most bonnet gas strut jobs are straightforward when the replacement is genuinely matched to the vehicle and mounting points. Problems usually start when a strut is chosen by length alone, fitted in the wrong orientation, or mounted without checking the load through the full opening arc.

Start with the correct bonnet strut

A gas strut is not a universal spring. Its extended length, compressed length, stroke, end fittings and force rating all affect how the bonnet behaves. A strut that looks close enough may hold the bonnet too low, bottom out before the hinges reach their stop, or place unnecessary load on thin bonnet metal.

Where possible, use the vehicle make, model, year and existing strut part number to identify the correct replacement. If the original strut is unavailable or the bonnet has been modified, take accurate measurements with the bonnet safely supported. Measure centre-to-centre between the mounting points with the bonnet fully open, then again at its lowest safe closed position. Record the bracket type, ball stud size and thread details as well.

Force is the measurement most often overlooked. It is normally marked in Newtons as N. A heavier bonnet, aftermarket bonnet scoop, added insulation or accessory lighting can change the force required. Too little force means the bonnet slowly drops or fails to rise. Too much force can make it difficult to close, strain hinges and cause the bonnet to spring upward abruptly.

What to check before bonnet support installation

Before removing anything, inspect the existing arrangement. Look at where each end of the strut attaches, the direction of the cylinder, and whether the mounting bracket is secured to a reinforced section. Photographing both sides before disassembly is useful, particularly on vehicles with different left and right brackets.

Check for worn ball studs, loose brackets, cracked welds and elongated mounting holes. Replacing a failed strut without addressing a loose ball stud only transfers the problem to the new component. On older utes, four-wheel drives and work vehicles, corrosion around hinge areas and guard-mounted brackets deserves close attention.

The bonnet must also be supported independently before a strut is removed. Use a solid prop, a suitably rated bonnet stand or have a second person hold it steady. Do not rely on one weak gas strut while removing the other. A bonnet can drop quickly once its support changes.

Confirm the mounting orientation

For most automotive applications, the gas strut cylinder should sit higher than the rod when the bonnet is closed. This generally keeps the internal seal lubricated and helps maximise service life. The original installation layout is the best guide unless the strut supplier specifies otherwise.

Orientation can be constrained by the vehicle design, so clearance matters just as much. Cycle the bonnet by hand after fitting and check that the strut body, rod and end fittings do not contact the guard, hinge, wiring, washer hose or sound insulation. A slight clash that occurs only near the closed position can quickly damage the rod seal.

How to fit bonnet gas struts

With the bonnet securely propped, installation should be controlled rather than rushed. Many replacement struts use socket ends that clip over ball studs. Others use eye fittings, pins or threaded ends. Follow the fitting style supplied rather than forcing parts that appear similar.

First, remove the retaining clip only far enough to release the old socket from its ball stud. In most cases, the clip stays attached to the socket and does not need to come right out. Use a small flat screwdriver carefully. Excessive leverage can distort the clip or scratch surrounding paintwork.

Remove one strut at a time. Attach the new strut to the fixed body-side mounting point first, then align the bonnet-side fitting. Press the socket squarely onto the ball stud until it clicks or seats fully. If a bracket uses bolts, start all fasteners by hand and tighten them to the vehicle manufacturer’s specified torque. Do not use the gas strut itself to pull misaligned mounting points into position.

Once both ends are connected, confirm that each retaining clip is engaged and the socket cannot be pulled from the ball stud by hand. Lower and raise the bonnet slowly for the first few cycles. This lets you identify binding, contact points or an incorrect open height before putting normal load through the system.

Do not compress or modify the strut

Gas struts are pressurised components. Never drill, heat, cut, puncture or attempt to refill one. Do not clamp the polished rod in a vice, as marks on the rod can damage the seal and lead to early failure. If the supplied length or force does not suit the application, stop and confirm the specification rather than trying to alter the strut.

Testing the finished installation

A fitted strut should assist the bonnet through the opening movement and hold it securely at the designed open position. It does not always need to lift the bonnet entirely from the latch position, especially with heavier bonnets. What matters is stable support once the bonnet is open and predictable movement throughout the travel.

Test the installation on level ground. Open the bonnet fully, leave it for several minutes and check for any gradual drop. Then lower it carefully and confirm it closes without excessive resistance or a sudden push in the final section of travel. Listen for clicking at the sockets and inspect the brackets while the bonnet is moving.

If the bonnet twists, rises unevenly or requires significant force to close, do not assume the struts will settle in. Recheck the part numbers, force rating, bracket positions and left-right fitment. Gas struts are commonly replaced in pairs because a new high-force strut paired with a tired unit can produce uneven loading and poor bonnet alignment.

When a custom bonnet support is the better option

Standard replacement struts suit many factory arrangements, but custom bonnet support systems are often required for modified vehicles, engine conversions, fibreglass bonnets, older vehicles and fabricated engine bays. The right design depends on bonnet weight, centre of gravity, hinge geometry, desired opening angle and available mounting space.

Mounting position changes the effective leverage of the strut. Moving a bracket only a small distance can greatly change how much force is needed and where the load is applied. That is why selecting the highest-force strut is not a reliable fix for a bonnet that will not stay open. It may solve one issue while creating hinge stress, distortion or difficult closing.

For a custom setup, provide the bonnet weight, the intended open angle, photos of the hinge and mounting areas, and the open and closed centre-to-centre measurements. Include details of the bracket material and any obstructions in the strut path. This gives a strut specialist enough information to recommend an appropriate force, length, end fitting and bracket arrangement.

Common faults after fitting

If a newly installed strut fails quickly, the cause is often external rather than the gas spring itself. Side-loading from misaligned brackets, a scored rod, incorrect orientation, contaminated ball sockets and overextended travel can all shorten working life. A bonnet used frequently in fleet, trade or workshop conditions may also need a higher-quality strut and hardware set than a lightly used passenger vehicle.

Keep the rod clean and avoid spraying it with heavy lubricant. Wipe away grit with a clean cloth, inspect brackets during routine servicing and replace damaged ball studs before they wear out the new sockets. These small checks are particularly worthwhile on vehicles exposed to dust, salt air, mud or regular wash-downs.

If the fitment details are unclear, Gas Struts can help confirm the measurements and hardware needed before installation. Getting the force and mounting geometry right at the start is the practical way to achieve a bonnet that stays where it should, every time you open it.

A trailer ramp that drops heavily, is difficult to lift or will not stay open is more than an inconvenience. It can slow down a job, damage hinges and create a real manual-handling risk. To fit trailer ramp struts properly, you need more than a pair with similar-looking end fittings. Correct force, closed and open lengths, mounting position and ramp weight all affect whether the finished setup works safely.

This is a practical job for many trailer owners and workshops, but it is not one to guess. Gas struts store significant force. A strut that is too strong can make the ramp hard to close and overload the mounting brackets; one that is too weak can leave the ramp uncontrolled or unable to remain raised.

Start with the ramp, not the old strut

If you are replacing an existing strut system that performed well before it failed, the original strut markings provide a useful starting point. Record the part number, extended length, compressed length, end fitting type and force rating in Newtons. A marking such as 900N refers to the force produced by the strut, not the ramp weight it can directly hold.

Do not assume an old strut is the correct specification simply because it physically fits. The trailer may have been modified, the ramp may have gained a spare wheel carrier or cladding, or the original installation may never have operated properly. When fitting a new pair to a ramp that has no struts, measure the actual application instead.

The key details are ramp width and construction, approximate ramp weight, hinge position, desired open angle, available mounting area and whether the ramp carries any equipment when open. Steel ramps, mesh ramps and fold-up loading ramps can have very different balance points even when their overall dimensions appear similar.

Measure before you fit trailer ramp struts

A gas strut works through geometry. Its support changes as the ramp moves, which is why mounting points matter just as much as the stated Newton rating. Measure with the ramp fully closed and then at its intended open position. Never rely on a ramp held up only by a person while taking measurements.

Support the ramp securely on stands, a forklift with suitable restraint or another safe mechanical support. With the ramp closed, measure the centre-to-centre distance between the proposed upper and lower mounting points. Repeat the measurement with the ramp open. These measurements determine the compressed and extended strut lengths required.

Allow a small margin at both ends of travel. A strut must not bottom out before the ramp is fully closed, as this can damage the strut, brackets or ramp structure. It should also not reach full extension before the ramp is at the intended open angle. Most applications need a little remaining stroke at full open and full closed positions.

Mounting angle affects leverage. A strut fitted too close to the hinge has less leverage and will generally require more force. Moving the mounting point further from the hinge increases leverage, but space, strut travel and bracket strength still need to be considered. Small changes in bracket location can have a large effect on how the ramp feels in use.

Check the force rating as a pair

Trailer ramps commonly use two struts, one on each side. The force rating is usually specified per strut, so two 700N struts provide a combined nominal force of 1,400N. That does not mean they will lift a 140 kg ramp at every position. The strut angle and distance from the hinge determine the usable lifting assistance.

Ramp weight should be checked rather than estimated where possible. A workshop can weigh the ramp or calculate it from material thickness and construction, but practical measurement is preferable. Also account for mud, water, ramps extensions, latches and any accessories that change the load.

For a heavy tailgate-style ramp, it is often better to use correctly located, higher-force struts with substantial brackets than to force an undersized strut into a poor mounting position. The trade-off is closing effort. The ramp should lift in a controlled manner but still be manageable to pull shut without excessive strain on latches or handles.

Choose the right strut and hardware

A trailer ramp installation needs gas struts suited to outdoor, high-use work. Look for quality sealed units with suitable corrosion protection and reliable end connections. For trailers used near the coast, on farms or on worksites, environmental exposure matters. Dust, water, vibration and road grime shorten the life of poor-quality components.

End fittings must match the brackets and allow the strut to move through its full arc without binding. Ball joints are common because they tolerate angular movement, while eye ends, clevis ends and pin mounts may suit particular ramp designs. Replace worn ball studs, loose pins and cracked brackets at the same time. A new strut cannot compensate for damaged hardware.

Brackets should be attached to structurally sound material, not thin sheet metal alone. Depending on the trailer design, this may mean welding to the ramp frame and chassis rail, using reinforced bolt-through plates or adding internal backing plates. The load is applied repeatedly each time the ramp opens and closes, so fatigue resistance is just as relevant as initial strength.

Gas Struts can assist with standard replacements and custom trailer ramp struts where the required length, force or end fittings do not match an off-the-shelf setup. Having accurate measurements and clear photos of the hinge area, brackets and existing strut markings will make specification faster.

Fitting procedure and safe orientation

Before installation, secure the trailer on level ground with the wheels chocked. Support the ramp independently. Remove any old struts only after the ramp is restrained, as failed struts may still retain some force and the ramp can move suddenly once they are disconnected.

Install the brackets and check their alignment before snapping the struts onto the ball studs or fitting the pins. The struts should move freely throughout the ramp arc without contacting mudguards, lights, chains, the trailer body or each other. Test the movement slowly by hand before relying on the struts to carry the ramp.

For most gas strut applications, fit the cylinder body uppermost when the ramp is closed, with the rod pointing downward. This keeps internal oil around the rod seal and helps lubrication during normal operation. There are exceptions where the installation angle or manufacturer specification requires another orientation, so confirm this if the struts will sit close to horizontal or operate in an unusual position.

Do not drill or weld near an installed gas strut. Heat can damage seals and pressurised units must never be punctured, crushed, opened or placed in a fire. If bracket welding is required, remove the struts first and protect nearby trailer wiring, paint and fuel-related components.

Test the ramp through its full travel

The first test should be controlled. With a clear area around the ramp, raise and lower it several times while observing the movement at both brackets. The ramp should not jump open, twist sideways, bind at the hinges or require a sudden hard pull near the end of travel.

Pay attention to the final stages. If the ramp stalls before opening fully, the struts may be too short, too weak or incorrectly positioned. If it pushes hard against the closed latches, the struts may be too strong, too long when compressed or mounted with too much leverage. Do not accept a setup that only works when forced.

Recheck fasteners after initial use, particularly on bolted installations. Vibration can reveal bracket movement that was not obvious in the workshop. Inspect struts during routine trailer maintenance for oil leakage, rod damage, loose end fittings and corrosion around mounts.

A correctly specified strut pair should reduce lifting effort without taking control away from the operator. Take the time to measure the ramp, support it safely during installation and confirm the geometry before committing to bracket positions. That is how you get a trailer ramp that is easier to handle, kinder to its hinges and dependable on the next job.