Second Hand Mercedes-Benz CLS Engine

The CLS has run across two main generations in the UK: the first-generation C219 ran from 2004 to 2010, and the second-generation C218 ran from 2011 to 2018 with a facelift in 2014. A third generation, the C257, followed from 2018 onwards. Knowing which generation your car belongs to is important because engines are not generally interchangeable across these boundaries.

Both years sit within the C218 generation (2011–2018), with the facelift arriving in 2014, so there is a real chance of compatibility if the engine codes match — the engine code is the most reliable guide, not the model year alone. However, ancillary fitments, mounts, and wiring loom connections can change mid-production even within a facelift cycle, so you should confirm those details directly with the breaker against your specific registration before buying.

The 350 and 250 badges denote entirely different engines — for example, the CLS 250 CDI uses a four-cylinder diesel (engine code OM651) while the CLS 350 uses a larger six-cylinder unit — so the badge directly reflects the engine fitted and you cannot swap between them without significant additional work. What does not matter for fitment is whether one car was a higher trim specification than the other; trim level alone has no bearing on engine compatibility. Always cross-reference the engine code on your V5 or a VIN check rather than relying solely on the badge.

The OM651 engine family was used across several Mercedes-Benz models including the E-Class W212 and C-Class W204, so an engine sharing the same code from one of those platforms may well be compatible with a CLS C218. That said, mounting points, ancillary brackets, and ECU pairing requirements can differ between platforms and model years, so confirm these specifics with the breaker using your exact registration before proceeding.

The CLS was predominantly sold in the UK with automatic gearboxes, but gearbox type can still influence which flywheel and ancillary components are attached to a donor engine, so you should tell the breaker whether your car is automatic or manual. The engine code remains the primary fitment guide, but flagging your gearbox type helps the breaker supply the engine in the correct configuration and avoids additional work at your end.

The C219 (2004–2010) and C218 (2011–2018) are distinct generations with different platforms, so engine swaps across this boundary are not straightforward and cannot be assumed to be compatible even if the displacement and fuel type appear similar. Engine codes changed between these generations, and ancillary systems, ECU architecture, and mounting arrangements differ significantly. You should confirm the engine code on your V5 and discuss cross-generation fitment directly with the breaker, as it is not something that can be guaranteed without checking against your specific registration.