Parts for your 2021 Subaru Impreza-Gas struts

2021 Subaru Impreza gas struts — what they do and when to replace them

Technical references point to gas struts being fitted to the 2021 Subaru Impreza 5‑Door (hatch), but not to the 4‑Door (sedan) boot or the bonnet. Subaru’s genuine parts catalogues list a gas‑charged “stay/rear gate support” for the hatch, while the sedan shows a “deck‑lid torsion bar” setup for the boot. Workshop and owner documentation for MY21 Impreza indicate the bonnet is held by a manual prop rod rather than struts. So, gas struts are relevant to the hatch’s rear gate only, sedan owners won’t find gas struts on the boot, and no factory bonnet struts are fitted.

On the 2021 Impreza hatch, the rear gate gas struts do the heavy lifting—literally. They counterbalance the weight of the tailgate so it opens smoothly, holds itself up, and closes with a controlled motion. They’re nitrogen‑charged dampers, sealed to keep dust and moisture out, and tuned so they won’t launch the gate skyward or let it crash down on a windy day.

As part of regular servicing, it’s worth giving the struts a quick once‑over. Wipe the shafts with a clean, dry cloth to remove grit, check for oil misting around the seals, and listen for any creaks or hissing. If the hatch starts to sag, needs a helping hand to rise, pops up only in warm weather, or thumps shut, the gas charge is likely on the way out. Because both struts age together, replace them as a pair.

A technician will support the hatch, swap the ball‑socket clips or bolts, and confirm smooth, even operation. There’s no re‑gassing routine for these units—once the internal pressure or seal integrity is gone, replacement is the reliable fix. In Australian and New Zealand conditions, many drivers see 5–8 years from a set, but high heat, frequent use, and coastal environments can shorten that.

• Care tips: don’t lubricate the shiny shafts (oil attracts grit and harms seals), keep the hinge area clean, and avoid forcing the hatch when iced up or loaded with snow.
• Safety: always support the gate during replacement and avoid working under a weak strut—use a prop or get a mate to help.

If you’ve got the 2021 Impreza Sedan, your boot uses torsion bars instead of gas struts—there’s nothing to service there beyond hinge lubrication and latch adjustment. The bonnet across both body styles uses a prop rod from factory, so bonnet gas struts don’t apply unless you’ve fitted an aftermarket kit.

Popular questions

How long do the 2021 Impreza hatch rear gas struts last?
Most owners can expect around 5–8 years, but high temperatures, frequent opening, and coastal air can bring that forward. If the hatch won’t stay up or lifts sluggishly, it’s time to replace them in pairs.

Can the factory gas struts be re‑gassed, or should they be replaced?
Factory units are sealed and not designed for re‑gassing. Once they lose pressure or show oil seepage, replacement is the dependable, cost‑effective option.

Does the 2021 Impreza have bonnet gas struts?
No. The bonnet uses a manual prop rod from factory. Only the 5‑Door hatch’s rear gate has gas struts, the Sedan’s boot uses torsion bars.