Home Mercedes M112 3.2L Engine

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

Manufacturer
Stuttgart-Bad Cannstatt Plant
Production years
1997-2015
Cylinder block material
Aluminum
Cylinder head material
Aluminum
Fuel type
Gasoline
Fuel system
Fuel injection
Configuration
V
Number of cylinders
6
Valves per cylinder
3
Valvetrain layout
SOHC
Bore, mm
89.9
Stroke, mm
84.0
Displacement, cc
3199
Type of internal combustion engine
Four-stroke, naturally aspirated
Compression Ratio
10
Power, hp
190/5600
218/5700
224/5600
Torque, lb ft
199/2750
229/3000
232/3000
Engine weight
Firing order
1-4-3-6-2-5
Engine oil weight
0W-30, 0W-40, 5W-30, 5W-40, 5W-50, 10W-40, 10W-50, 15W-40, 15W-50
Engine oil capacity, liter
8.0
Oil change interval, mile
6,000
Applications
Mercedes-Benz C 320 W203, Mercedes-Benz CLK 320 C208, Mercedes-Benz CLK 320 C209, Mercedes-Benz E 320 W210, Mercedes-Benz E 320 W211, Mercedes-Benz ML 320 W163, Mercedes-Benz S 320 W220, Mercedes-Benz SL 320 R129, Mercedes-Benz SLK 320 R170, Mercedes-Benz Viano 3.0/Vito 119 W639, Mercedes-Benz Viano 3.2/Vito 122 W639

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.