Second Hand BMW 4 Series Gearbox

The BMW 4 Series F32/F33/F36 ran from 2013 to 2020, with a facelift in 2017 that brought minor cosmetic and equipment updates. A second generation, the G22/G23/G26, launched in 2020 and is a completely different platform. When sourcing a gearbox, knowing which generation you have is essential, as parts are not interchangeable between the F-series and G-series.

Both the 2015 and 2019 4 Series sit within the F32/F33/F36 generation (2013–2020), with the facelift occurring in 2017, so you are within the same generation boundary. Whether the gearbox crosses that 2017 facelift line without issue depends on your exact engine code, and there can be ancillary and mounting changes mid-production that are not always obvious — confirm compatibility with the breaker against your registration. The engine code, found on your V5 or via a VIN check, is the single most useful detail you can supply.

BMW's 4 Series shares its platform and engines with the contemporary 3 Series F30, so gearboxes for the same engine code can often be shared between the two. What matters above all is that the engine codes match exactly, not the badge on the bonnet. Confirm this directly with the breaker using your registration or engine code, as mounting brackets and ancillary connections can vary even within closely related models.

Yes, these badges reflect different engine codes and sometimes different gearbox units, so a gearbox from a 420i is not automatically compatible with a 430i even though both are petrol models. The engine code is what the breaker will match against, not the badge, so check your V5 or run a VIN check to get the exact code before requesting quotes. Fuel type also matters — a diesel 420d gearbox will not suit a petrol 420i even if the year and body style are identical.

Trim level does not affect gearbox fitment; the gearbox is determined by your engine code, fuel type, and whether the car left the factory with a manual or automatic transmission. An M Sport 420d and an SE 420d with the same engine code and gearbox type take the same unit. You may find cosmetic differences on parts stripped from different trims, but for a mechanical component like the gearbox this is irrelevant — just make sure the engine code and transmission type match.

ECU pairing and any immobiliser coding requirements for a replacement gearbox are not something we can confirm as fact here, as this varies by model, year, and the specific control units involved. You should raise this directly with the breaker and your fitting garage before purchasing, so you understand any additional work required. Getting this confirmed upfront avoids unexpected costs after the part has already been fitted.