Cheap Mercedes-Benz SLK Catalytic Converter

The SLK ran across three generations: the R170 (1996–2004), the R171 (2004–2011), and the R172 (2011–2016), and each generation used a different platform, engine family, and exhaust architecture, so cats do not carry across these boundaries. Even within a generation, the engine code is the critical factor – a 200K unit and a 350 unit will have different catalyst configurations. Confirm the exact engine code from your registration against what the breaker has before committing.

The R171 received a facelift around 2008, and while the core engine codes were largely carried over, emissions calibration and exhaust component specifications can vary across a facelift refresh. Whether a specific cat from a pre-2008 car interchanges with a post-2008 car is strong confirm-with-breaker territory – share your registration and ask the breaker to match engine codes precisely.

Yes, all petrol-engined SLK variants across the R170, R171, and R172 generations were fitted with a catalytic converter as standard emissions equipment. The R172 also introduced diesel variants (the SLK 200 CDI and 250 CDI), which use a diesel oxidation catalyst and particulate filter arrangement rather than a traditional three-way cat, so the correct part depends on whether your car is petrol or diesel.

Trim or specification level in itself makes no difference to catalyst fitment, but the engine is everything – the SLK 200 Kompressor and the SLK 350 use entirely different engines with different exhaust systems, so they absolutely require different catalytic converters. Focus on matching the engine code shown on your V5C or via a registration lookup rather than the trim badge alone.

The R172 ran from 2011 to 2016, and the key variables within that span are the engine code and the Euro emissions standard applicable to your specific car's registration date, as Euro 6 requirements began influencing component specs from around 2014 onwards. Whether a 2015 cat will physically and legally interchange with a 2012 car's exhaust system is something to confirm with the breaker against both registration numbers, since fitting a cat calibrated for the wrong emissions era could cause MOT failure.

Yes, significantly – petrol SLKs use a three-way catalytic converter, while the diesel SLK 200 CDI and 250 CDI models introduced on the R172 use a diesel oxidation catalyst as part of a different after-treatment system that also includes a diesel particulate filter. These parts are not interchangeable between petrol and diesel cars, so always confirm fuel type, engine code, and emissions specification with your breaker before ordering.