Overview
The Mercedes-Benz M104 is a straight-6 automobile engine produced from 1989 through 1999. It has a double overhead cam design with 4 valves per cylinder, and used a crossflow cylinder head. It replaced the M103 and was replaced by the M112 V6 starting in 1997. The bore spacing on all M104 engines is the same as M103 engines.
2.8 L M104.900
As Mercedes needed a compact 6-cylinder for their Vito, they agreed with Volkswagen to use their VR6 engine, which they then designated M104.900. An agreement was reached and the engines were sold semi-completed to Mercedes-Benz. This version is unrelated to other engines designated M104. Only the engine cover and aircleaner housing is by Mercedes-Benz.
3.0 L M104.98x
This 24v was introduced as a sports car resp. top model completing the line-up of M103 12V engines. The M104 featured dual overhead camshafts and four valves per cylinder. The M103 and M104.98x were later replaced by the 2.8-litre and 3.2-litre versions of the M104.
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