Boot and Bonnet Gas Strut Buying Guide
Ultimo aggiornamento: 24 aprile 2026
Gas struts (gas springs) use nitrogen gas under pressure to provide a controlled extending force that assists in opening and holding bonnets, tailgates, boot lids, and other panels in the open position. A failed gas strut will allow the panel to fall or require manual propping, which is a safety hazard and an MOT advisory.
How gas struts work
A gas strut consists of a sealed tube filled with nitrogen gas and, in most types, a small amount of hydraulic oil for lubrication. As the strut is compressed (closing the bonnet or tailgate), the gas is compressed further, storing energy that is released smoothly as the panel is opened. The oil controls the damping rate, preventing the strut from extending violently and allowing the panel to open at a controlled speed.
Gas struts are rated by their extended and compressed lengths (stroke) and their force rating in Newtons. Both parameters must match the original fitment for the panel to open fully and hold correctly.
When to replace gas struts
A gas strut that no longer holds the panel open, or one that requires the panel to be lifted to the top before it will stay up, has lost its gas charge through a failed seal. Gas pressure cannot be recharged — the unit is replaced as a whole. Struts typically last 5–10 years depending on use frequency and environmental exposure.
When one strut on a paired installation (e.g. two tailgate struts) fails, replacing both at once ensures matched force and prevents the working strut from being overloaded trying to hold the full panel weight alone.
- Panel will not stay open without manual support
- Panel drops or falls slowly (low gas charge)
- Visible oil leak on rod or from seal
- Replace in pairs for matched performance
- Struts are not rechargeable — replace the unit
Buying the right strut
Gas struts are highly position and model-specific. End fitting type (ball socket, clevis, or eye), extended length, compressed length, and force rating must all match. Use the registration lookup to confirm the correct gas strut for your vehicle's bonnet, tailgate, or boot. Free UK delivery on orders over £99.
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Tailgate or bonnet not staying up? How to measure force rating, strut length, and ball-end fittings — and why cheap gas struts fail quickly.
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Domande frequenti
What are the signs that a gas strut needs replacing?
A boot, bonnet or tailgate that slowly drops, will not stay up on its own, or feels weak when lifting usually means the gas strut has lost pressure. Struts often fail in pairs, so both sides may need replacing together.
What does a gas strut do?
A gas strut is a sealed gas-filled support that holds up a boot, bonnet, tailgate or similar panel and makes it easier to open and close. Over time the internal gas pressure drops, which is why support gradually weakens.
How do I find the right gas strut for my car?
Gas struts are matched to the panel they support by length and force rating, which differs between models. Enter your registration above to see struts confirmed to fit your vehicle, and replace them in pairs for even support.
How much does a gas strut cost?
The price of a gas strut depends on your exact vehicle and the brand you choose. Enter your registration above to see parts confirmed to fit, then compare prices from the brands we stock on this page. Free UK delivery on orders over £99.
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Split or cracked CV boots lead to joint failure — how to spot grease flinging, boot types and sizes, and replacing a boot without removing the driveshaft.
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Guida ai cuscinetti ruotaRonzio, rumore sordo, scricchiolio — come diagnosticare un cuscinetto ruota difettoso sulla tua auto e capire le opzioni di sostituzione.
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