Second Hand Mercedes-Benz GLS Throttle Body

It depends on the engine variant. Petrol-engined GLS models (such as those with the M276 or M178 V8 engine codes) do use a throttle body as part of the intake system, so the part genuinely exists on those variants. However, diesel GLS models (for example those with the OM642 or OM656 engine codes) do not use a conventional throttle body in the same way as a petrol engine, so if you have a diesel GLS you are unlikely to need this part — confirm with a breaker what you actually need if you are diagnosing an air management or EGR-related fault on a diesel.

The GLS has two main generations: the first-generation X166, produced from 2016 to 2019, and the second-generation X167, which launched in 2020 and is still current. A 2020 GLS is an X167, which is a completely different platform from the X166, so a throttle body from a pre-2020 model is very unlikely to be compatible even if the engine displacement looks similar on paper. Always match by engine code rather than year, and confirm cross-generation compatibility with the breaker against your registration.

Both are first-generation X166 models, so fitment is more likely provided the engine codes match exactly — the engine code is the most important detail here, not the model year alone. There were different petrol engines available within the X166 range, so a unit from a GLS 400 (M276 engine) and a GLS 63 AMG (M157 or M178 engine) will not be interchangeable. Confirm the exact engine code from your V5 or a VIN check and supply it to the breaker before purchasing.

No, trim level does not affect throttle body fitment — AMG Line, standard, and other trim designations relate to cosmetic and equipment differences, not engine internals. What matters is the engine code, which can be the same across different trim grades. Focus entirely on matching the engine code from your V5 or VIN check, and ignore the trim badge when searching.

The GLS 350d uses a diesel engine (typically the OM642 V6 diesel) and diesel engines do not use a throttle body in the conventional petrol sense, so this part would not normally be replaced on your vehicle. If you are experiencing symptoms such as rough idling or poor throttle response, the fault is more likely related to the EGR valve, swirl flaps, intake manifold, or a sensor rather than a throttle body. Speak to a breaker or mechanic about the specific symptoms so they can point you toward the correct part.

The GLS has only ever been offered with an automatic gearbox in the UK market, so gearbox type is not a practical concern when sourcing a used throttle body for this model. The engine code remains the critical matching factor regardless. Confirm the engine code with your breaker to ensure the part is suitable for your specific vehicle.