Used Mercedes-Benz SLK Gearbox

The SLK R171 generation ran from 2004 to 2011, so both years sit within the same generation — but fitment still depends on matching the engine code exactly, not just the year, since different engines (for example the 1.8 kompressor versus the 3.5 V6) used different gearboxes and ratios. Pull the engine code from your V5 or a VIN check and give it to the breaker so they can match it precisely. Never assume year-to-year compatibility without confirming the engine code matches.

The R171 received a facelift around 2008, and while the generation boundary is the same chassis, ancillary mountings and ECU pairing can change mid-production in ways that are not always publicly documented. Name the exact engine code from your V5 and give it to the breaker to confirm whether a pre- or post-facelift unit crosses that boundary cleanly. Because ECU and immobiliser coding is also a variable, confirm both electrical compatibility and physical fitment with the breaker against your registration.

The R170 (1996–2004) and R171 (2004–2011) are separate generations with different engines, gearbox bell housings, and control systems, so a straight swap across that generation boundary is very unlikely. Confirm with a breaker against both registrations before purchasing anything, as mixing generations on a mechanical component like a gearbox rarely works without significant modification.

Trim or badge level (200, 280, 350 and so on) reflects the engine fitted, which directly changes which gearbox you need — a 350 V6 unit will not bolt to a 200 kompressor engine, so these are not interchangeable. Identify your engine code from the V5 rather than relying on the badge, and match that code when sourcing a replacement. The badge is a useful starting point but the engine code is the only reliable guide.

Yes, manual and automatic gearboxes are entirely different units and are not interchangeable even on the same engine code, so you must know which type your car has before approaching a breaker. The SLK was offered with both manual and automatic (including the 7G-Tronic on later R171 models) depending on engine and year. State your gearbox type clearly alongside your engine code when getting a quote.

A matching engine code is the strongest indicator that a used gearbox will physically fit, but confirm with the breaker that the unit comes from a car with the same registration or engine code on record, as mounting and ancillary details can vary within a production run without a formal model change. ECU pairing and immobiliser coding are separate considerations that your breaker or an independent Mercedes specialist should advise on for your specific car. Always confirm fitment against your registration before purchasing.