Parts for your 2018 Lexus Is-Strut mounts

2018 Lexus IS strut mounts — are they actually used?

Short answer: no, “strut mounts” aren’t a relevant part on the 2018 Lexus IS. According to Lexus’ technical literature for the XE30 series — including the New Car Features (NCF) manual and the Toyota/Lexus Repair Manual (RM) — the IS runs a double-wishbone front suspension and a multi-link rear. That layout doesn’t use a MacPherson strut, so there’s no traditional strut top mount with an integrated steering bearing.

What the 2018 IS does have are shock absorber upper mounts (often called insulators or suspension support sub-assemblies). In a double-wishbone front end, the steering axis is formed by the ball joints and control arms, not by a rotating strut. So the top mounting of the damper is simply a rubberised support to isolate noise and vibration, it isn’t a steerable bearing like a strut mount on a MacPherson setup.

This is why some parts catalogues can be confusing. They’ll label “strut mounts” generically, but for the 2018 IS they’re referring to the shock absorber mount/insulator. If shopping, look for terms like “front suspension support (insulator)”, “rear shock absorber support” or equivalent. If the car is fitted with Adaptive Variable Suspension (AVS), make sure the mount is matched to AVS hardware.

Why Lexus chose this arrangement comes down to dynamics and refinement. The double-wishbone design offers precise camber control and sharper steering feel — something the IS line is known for — without needing a strut tower-mounted, steerable top bearing.

• Typical signs the shock mounts/insulators are tired: thuds or knocks over sharp bumps, increased cabin vibration, or visible perishing/cracking of the rubber.
• Because the mount doesn’t carry a steering bearing, heavy or notchy steering is unlikely to be caused by these mounts.
• If the damper is leaking oil, that’s a shock absorber issue rather than the mount itself.

Service advice for Aussie and Kiwi roads: inspect the shock mounts/insulators around 60,000–100,000 km, or sooner if the car sees rough surfaces. Replace in axle pairs where practical, use quality OEM or reputable aftermarket parts, and have an alignment check after suspension work to keep tyre wear even and handling tidy.

Popular questions about 2018 Lexus IS strut mounts

Does a 2018 Lexus IS have strut mounts?
No. The 2018 IS uses a double-wishbone front and multi-link rear suspension, so it has shock absorber upper mounts/insulators rather than MacPherson-style strut top mounts with a steering bearing.

What part do I buy instead of a strut mount for my 2018 IS?
Search for the shock absorber upper mount/insulator (often listed as a “front suspension support sub-assembly” and “rear shock absorber support”). If the vehicle has AVS, make sure the mount is compatible.

What symptoms suggest these mounts need replacing?
Listen for knocks over bumps, feel for extra vibration, and check for perished rubber. Steering-weight issues are usually unrelated, since the mount doesn’t rotate. If you see damper oil leaks, that’s a shock, not a mount, problem.