Mercedes M112 3.2L Engine Specs, Problems & Reliability

The M112 E32 V6 engine replaced inline 6-cylinder M104 E32 series on the production line in 1997. The new 112-series includes the following engines: E24 M112, M112 E26, E28 M112, M112 E32 ML, and M112 E37.

The engine is designed in V configuration (the cylinder bank's angle is 90 degrees). That is allowed to unify mostly all essential parts of the V8 M113 engine. The M112 E32 has a balancer shaft. The cylinder block is made of light aluminum alloy instead of heavy but reliable cast iron. On top of each cylinder bank, there are aluminum cylinder heads with three valves per cylinder (two intake valves and one exhaust valve), hydraulic lifters/tappets, and one camshaft on top of each head (SOHC design). The M112 engine uses a timing chain but doesn't have a variable valve timing system. On the intake side, this engine comes with a variable geometry intake manifold.

The next step in the development of V6 Mercedes engines became the M272 KE/DE 35 engine appeared in 2004.

Engine Specs

M112 E32 3.2l Engine Problems and Reliability

1. High oil consumption. The cause of the severe oil consumption is often the wear of valve stem seals. The next variant is contaminated ventilation of crankcase gases.
2. Oil leaks. The weak point in the M112 is the seal of the oil heat exchanger.

Modifications

M112.940 (1997 - 2003) - version with power of 218 hp at 5700 rpm. This motor for Mercedes-Benz CLK 320 C208.
M112.941 (1997 - 2002) - for Mercedes-Benz E 320 W210. Power is 224 hp.
M112.942 (1997 - 2005) - M112.940 for Mercedes-Benz ML 320 W163.
M112.944 (1998 - 2002) - M112.941 for Mercedes-Benz S 320 W220.
M112.951 (2003 - 2015) - version for Mercedes-Benz Vito 119/Viano 3.0 W639, 190 hp.