Lexus RX Engine Mount: Specs, Fitment & Common Faults

Confirmed: a genuine Technical Service Bulletin addresses an exhaust drone that can mimic a bad engine mount — plus an alarming, honest account of a vibration so severe and unresolved that Lexus itself acknowledged the issue without having a fix.

Illustration for editorial purposes

OEM Part Numbers

Accuracy note: we weren't able to verify a confident Lexus RX engine mount part number at the time of writing. Please confirm the correct part via a Lexus dealer or parts specialist using your VIN.

The Part That Quietly Absorbs Everything

Engine mounts do a genuinely thankless job — holding a violently vibrating engine in place while isolating that vibration from the cabin — and when they wear out, the change is often gradual enough that owners adjust to it without realising something's actually wrong.

Before you buy: engine mount design and quantity vary by engine size and transmission type. Always confirm against your VIN before ordering.

What It Does

Engine mounts secure the engine and transmission to the chassis while absorbing vibration and movement, preventing that vibration from transferring directly into the cabin. Most versions of the RX use several mounts working together — typically at least one on each side of the engine plus a torque mount — and a single failed mount can throw off the whole assembly's balance.

Fitment & Compatibility

Mount design and positioning differ between engine sizes and transmission types (manual versus automatic) of the RX. Always confirm the exact mounts fitted to your specific engine and transmission combination before ordering, since manual and automatic versions often use different mount designs even on the same engine. Whether you're sourcing a replacement engine mount for your Lexus RX from a dealer, specialist, or online marketplace, always check compatibility against your registration or VIN before buying, and confirm you're ordering the correct side — driver's side (RH in the UK) or passenger side (LH in the UK) — since these are not interchangeable.

Common Faults

Symptoms of Failure

Noticeable vibration through the cabin, especially at idle — often the earliest and clearest sign of a worn mount.
Clunking noise when accelerating or braking — points to a mount no longer properly restraining engine movement.
Visible engine movement when revving in neutral — a worn or broken mount can allow far more movement than normal.
Increased noise, especially over bumps — a failing mount can let the engine knock against surrounding components.

DIY Replacement Difficulty

This is a moderate-to-difficult DIY job depending on which mount needs replacing — some are easily accessible, while others require supporting the engine's weight with a jack or hoist while the mount is removed and replaced. Getting this step wrong risks damage to the engine or surrounding components. Expect 1–3 hours depending on which mount and how accessible it is on your specific engine layout.

Confirmed: A Genuine Technical Service Bulletin Worth Checking First

If you're facing a vibration while accelerating on a 2016-2018 model specifically, this is genuinely worth checking before assuming the engine mount is at fault: a confirmed technical service bulletin addresses an exhaust drone issue that can feel remarkably similar to a bad engine mount, worth ruling out first since it's a genuinely different repair. It's also genuinely important to know before ordering a replacement front mount: the gas-engine mount, a specific part number, does not fit the hybrid variant at all, so it's worth confirming your exact powertrain before purchasing a replacement, since fitting the wrong one simply won't work.

A genuinely alarming, honest documented account worth knowing about how severe this can become: one directly documented case saw an engine mount replaced due to excessive vibration at low RPM, only for a very loud noise and vibration on acceleration to persist regardless — with Lexus reportedly aware of the situation but not yet having a solution at the time. The owner eventually gave up entirely and switched to a different manufacturer as a result. It's genuinely worth knowing this specific issue has been documented as severe enough to frustrate at least one owner into abandoning the brand, worth pushing for a proper, thorough diagnosis rather than accepting a straightforward mount swap if the vibration doesn't fully resolve.

It's also genuinely worth knowing some practical diagnostic points: shifting into neutral or park and seeing whether the vibration disappears is a useful way to help confirm a mount is genuinely the cause, since these mounts are fluid-filled, and a visual check for black or dark oily residue on the mount itself or the subframe beneath it can confirm a failure, as a leaking mount has lost its damping ability. Worth knowing these mounts have been documented leaking at surprisingly low mileage, sometimes as little as 57,000 miles.

OEM vs. Aftermarket

Reputable aftermarket engine mounts are generally a safe, cost-effective alternative to OEM parts, provided they match your exact engine and transmission specification. This is one area where cheap, poorly designed mounts can genuinely accelerate wear on adjacent components, so it's worth choosing an established brand over the very cheapest option available.

More Lexus Engine Mount Guides

The same part, covered across other Lexus models.