What Are Lift Supports and How Do I Choose the Right Ones in 2026?

Lift supports are pneumatic devices designed to provide a controlled, counterbalanced force to assist in the opening and holding of heavy objects like vehicle tailgates, machine guards, or storage bed frames. They rely on an internal charge of compressed nitrogen gas and a small amount of oil for damping, which prevents the controlled load from opening or closing with excessive force.

How Do I Identify the Correct Lift Support for My Application?

Identify the correct lift support by measuring the extended and compressed lengths, identifying the end fitting type, and reading the force in Newtons.

Which Dimensions Must I Measure First?

Measure the eye-to-eye length while fully extended, the total stroke length, and the diameter of the cylinder body for an accurate match.

Before purchasing, confirm the extended length from the centre of one end fitting to the centre of the other. The stroke length—the difference between extended and compressed states—is equally vital to ensure the hatch or lid can open to its full design range.

Why Does the Newton Force Rating Matter?

The Newton rating dictates the lifting capacity, where 1 Newton equals approximately 0.1 kilograms of force supported by the unit.

Many DIYers make the mistake of choosing supports based on physical size alone, ignoring the specific force output. If your current lift supports are weak, refer to the markings on the body, which typically state the force in Newtons (e.g., 500N). If the label is faded, use our gas spring force calculator to determine your requirements.

What Are the Common Failure Modes for Lift Supports?

Common failure modes include seal leakage causing pressure loss, corrosion on the chrome rod, or damage to the plastic end fittings.

Why Do Lift Supports Lose Their Lifting Power?

Nitrogen gas slowly permeates through the internal seals over time, leading to a gradual loss of pressure and eventual unit failure.

You may notice the hatch drifting downward or refusing to stay open entirely. This is a natural consequence of the nitrogen charge depleting, which usually occurs after several years of service. For a detailed look at why this happens, review our guide on diagnosing gas strut issues.

Can I Repair a Lift Support That Has Failed?

Lift supports are sealed, non-serviceable units that must be replaced as complete assemblies once the internal pressure is lost.

Attempts to drill or modify a cylinder are extremely dangerous due to the high-pressure gas contained within. If a unit is failing, it is more cost-effective and safer to replace it with a new component matched to your original specification.

How Do I Install New Lift Supports Safely?

Install supports by removing the old clips, securing the new unit into the mounting brackets, and verifying the orientation is correct.

Do I Need Professional Tools to Replace Them?

Standard screwdrivers are usually sufficient to pry open the retaining clips on ball-socket style end fittings during the replacement.

Most automotive and furniture supports use simple metal clips that lock the socket onto a ball stud. Ensure the hatch is fully propped open with a timber or a second person before removing the old units, as the panel may fall unexpectedly once a single support is disconnected.

Does the Mounting Orientation Affect Performance?

Mount lift supports with the piston rod facing downward to keep internal seals lubricated by the oil reservoir during normal operation.

If you mount them upside down, the oil can flow away from the seal, leading to premature drying, noise, and eventual failure. Always check the manufacturer markings if you are uncertain about the specific design constraints of your component. For more on installation, see our car boot strut replacement guide.

Frequently Asked Questions About Lift Supports

Find quick answers regarding gas-charged lift supports, including maintenance, safety, and proper procurement for industrial applications.

Is it necessary to replace both supports simultaneously?

Yes, replacing supports in pairs ensures that both units share the load equally, preventing premature wear and mechanical stress on hinges.

What grade of steel should I choose for outdoor use?

Use 316-grade stainless steel lift supports for marine or coastal environments to prevent the corrosion of the piston rod and end fittings.

Can I use a stronger support if the original is discontinued?

You can slightly increase force if necessary, but excessive force may cause damage to hinges or make the lid impossible to close manually.

How to Calculate the Required Lift Support Force

Determine the needed Newton rating by considering the weight of the lid, its centre of gravity, and the mounting geometry.

First, measure the weight (W) of the object in kilograms and convert to Newtons (W × 9.81). Then calculate the moment about the hinge: M = W × d, where d is the horizontal distance from the hinge to the object’s centre of gravity when the lid is closed. The lift support force (F) needed at its mounting point is F = M / L, where L is the perpendicular distance from the hinge to the support’s line of action (usually the distance between hinge and support mounting point). Choose a support with a force rating slightly above this value to account for friction and safety margin.

For example, a 10 kg tailgate with its centre of gravity 0.2 m from the hinge and a support mounted 0.3 m from the hinge requires F = (10 × 9.81 × 0.2) / 0.3 ≈ 65 N. Selecting a 70 N or 80 N unit ensures reliable operation.