The M57 is a water-cooled and turbocharged inline six cylinder diesel engine with
common rail injection. It was revised twice during its production time. It is based on its predecessor
M51. The block and the
crankcase of the first M57 engines and the TÜ (
Technische Überarbeitung = revision) engines are made of cast iron, whilst the TÜ2 engines are made of aluminium instead. The
combustion chamber was also changed in the TÜ2. The injection pressure is in the non TÜ engine, whilst all other engines use a pressure of . For fuel injection, magnetic injectors are used, except from the TÜ2 OL and TOP engines, which make use of piezo injectors. The common-rail-system is made by Bosch and also controlled by a Bosch DDE 4 ECU for non TÜ and DDE 5 ECU for TÜ. All models are equipped with turbocharger and an intercooler. The 2.9L M57, which is found in E39 530d and E38 730d, as well as early models of E46 330d and E53 X5, is equipped with one
Garrett GT2556V turbocharger. The 2.5L M57 non TÜ uses a Garrett GT2052V turbocharger, the 2.5L M57TÜ uses a Garrett GT2056V turbocharger, the 3.0L M57TÜ a Garrett GT2260V turbocharger, the M57TÜ2 a Garrett GTB2260VK turbocharger, whilst the M57D30TÜTOP sports a
BorgWarner KP39 high-pressure and a K26 low-pressure turbocharger. The compression ratio reaches from 16.5:1 to 18.0:1, M57 engines with higher power output and more than one turbocharger have a lower compression ratio. Every cylinder has two inlet and two exhaust valves as well as two chain-driven overhead camshafts. The redline is 4750 rpm. ==Technical data==