Parts for your 2018 Lexus Is-Gas struts

2018 Lexus IS gas-struts: what they do and when to replace them

Based on Lexus technical references — the Lexus Electronic Parts Catalogue (EPC) and the 2018 Lexus IS Repair Manual (Body: Hood/Bonnet and Luggage Compartment sections) for the XE30 series (ASE3#/GSE3#/AVE3#) — the 2018 Lexus IS uses gas‑charged lift struts on the bonnet, while the sedan’s boot lid is supported by gooseneck hinges with torsion bars and does not use gas struts. So, gas‑struts are absolutely relevant to the bonnet on this model.

Those bonnet gas‑struts quietly shoulder the heavy lifting every time the bonnet is opened. They’re nitrogen‑charged dampers that control the lift and prevent slam‑down, making under‑bonnet checks a breeze and keeping hands safe while working around the engine bay.

There’s no fixed service interval for bonnet struts, but like any sealed hydraulic component they lose charge over time. Heat cycles, age, and grit on the rod seals all contribute. Most owners notice the first signs on colder mornings: the bonnet won’t stay fully up or drifts down. A light oil mist around the rod or a jerky opening motion are other giveaways.

When it’s time to sort them, replacement is straightforward for a competent DIYer, but it’s still a two‑hand job: support the bonnet securely with a prop or helper, then swap the struts one side at a time. They’re designed to be replaced as a pair to keep lift balanced and hinge loads even. Re‑gassing isn’t recommended, once performance drops, new units are the reliable fix.

• Choose quality OEM or equivalent struts with the correct force rating for the IS bonnet.
• Inspect the ball studs and clips, renew any fatigued hardware while you’re there.
• Keep the chrome rods clean, don’t grease them — it attracts dust and can damage seals.

For day‑to‑day care, just give the struts a quick wipe during services and check that the bonnet lifts smoothly and holds at full extension. If the bonnet needs a hand to rise, or starts to creep down while you’re topping up fluids, it’s time to replace them. Given the modest cost and the safety factor, fresh bonnet struts are a smart bit of preventative maintenance on any 2018 Lexus IS.

Does a 2018 Lexus IS have gas-struts from factory?

Yes. The bonnet uses gas‑charged lift struts. The boot lid on the sedan uses torsion bars rather than gas struts, which is normal for this body style.

How long do bonnet struts last on a 2018 Lexus IS?

There’s no set lifespan, but many last 5–10 years depending on climate and use. Cold weather and frequent opening can shorten life. Replace them when the bonnet no longer stays up or feels weak.

Can bonnet struts be re-gassed, or should they be replaced?

On the IS, replacement is the go. They’re sealed units, re‑gassing isn’t a reliable or factory‑approved repair. Fit a quality matched pair for proper lift and safety.