Reconditioned Transfer Cases

Which engine code matches which reconditioned transfer case?

With a transfer case, the vehicle model alone is not enough to identify the correct part: it is the engine code, stamped on the block, that determines the exact reference. An X5 diesel can carry an M57D30, an N57D30, an N57D30A, an N57D30B or a B57D30 depending on the year of production — five distinct codes, five potentially different transfer cases. The range covered here spans from 1999 to 2021, across more than twenty models from BMW, Mitsubishi, Hyundai, Kia, Land Rover, Mercedes-Benz, Jeep, Nissan, Audi, Ford, Toyota and other manufacturers.

Diesel and petrol: the main engine code families

The vast majority of transfer cases in this collection cover diesel engines. For BMW, the codes 306D2, 306D3, 306D5, M57D30, N57D30, N57D30A, N57D30B and B57D30 all correspond to the 3.0d, but they span successive generations of the 6-cylinder in-line unit: confusing an M57 with an N57 leads directly to a mechanical incompatibility. On the petrol side for BMW, the codes M54B30, N52B30, N55B30A and B58B30A are fitted to the 3.0i across the Série 3, Série 5 and X-models — again, each generation of block requires its own transfer case. For the Audi S3 2.0 TFSI, the codes CDLA, CDLB and CJXC coexist across closely related model years. On the Ford Kuga 2.0 TDCi, six codes are recorded: G6DG, T7MA, T7MB, TXDA, UFDA and UFWA — a typical case where the registration year is not sufficient and only the engine code resolves the ambiguity.

Special cases and available purchasing options

Certain non-European models have their own engine families: the Mitsubishi L200 2.5 DI-D is based on the 4D56, the Isuzu D-Max 3.0 DDi on the 4JJ1 and 4JJ3, the Nissan Patrol 3.0 dCi on the ZD30DDTi and the Toyota Land Cruiser 3.0 D-4D on the 1KD-FTV. These references are available on an exchange basis. For parts with a specific transfer number, or in cases where the standard exchange is not suitable, rebuilding your own transfer case is an alternative: the original unit is reconditioned and then returned to you, avoiding any electronic or mechanical compatibility issues associated with a cross-replacement.