Used Mercedes-Benz GLS Gearbox Mount

Yes, the GLS has a gearbox mount — it is a rubber-and-metal bushing that supports the transmission casing against the subframe or body, damping vibration and holding the gearbox in alignment. Because every GLS variant sold in the UK uses a multi-speed automatic gearbox and four-wheel drive (4MATIC), the mount exists on all of them. If you were looking at a purely manual or front-wheel-drive layout you would need to rethink, but that does not apply to the GLS.

The X166 and X167 are distinct platforms with different engine bay packaging, so a mount from the first generation should not be assumed to fit the second. Name the generation boundary to your breaker — X166 up to 2019, X167 from 2019 — and they can cross-reference against your registration. Never assume a part crosses a generation boundary without confirmation from the breaker.

Yes, engine code matters more than the badge or displacement name, because different engines (for example the OM656 diesel versus the M176 petrol) sit in slightly different positions and may use different transmission pairings, which can alter mounting points and bracket geometry. Check your V5 or run a VIN check to get the exact engine code, then supply that to the breaker alongside your registration. Quoting the engine code is the single most useful thing you can do to avoid being sent the wrong part.

Fuel type matters because petrol and diesel variants of the GLS use different engine and transmission combinations, which can mean different mounting hardware and bracket designs. Always tell your breaker whether you have a diesel (for example a 350d or 400d) or a petrol (for example a 400 or 580), and back that up with the engine code from your V5. Do not assume a mount from a diesel donor car will drop straight onto a petrol vehicle or vice versa.

Trim level on its own does not affect the gearbox mount, because this is a mechanical component that follows the engine and transmission specification rather than the trim pack. An AMG Line GLS shares its drivetrain with a non-AMG-Line car of the same engine code, so the mount should be the same. The exception worth noting is the full AMG GLS 63, which uses a different engine entirely, so always confirm the engine code with your breaker rather than relying on the trim badge alone.

A 2018 GLS falls within the X166 generation, which ran from 2016 to 2019 in the UK before the X167 replaced it. Year matters within a generation because Mercedes-Benz occasionally made running changes to ancillary and mounting hardware during production, so a 2016 donor car is not guaranteed to be identical to a 2018 one. Confirm against your exact registration with the breaker, who can check the full VIN to identify any mid-run changes.