OM315

Compare it with what it replaced. The pre-war L 6500 used the OM 57, eleven-and-a-fifth liters giving 150 PS at 1,700 rpm. The OM 315 gave 145 PS from 8.3 liters at 2,100 — five horsepower down on paper, yet the lorry ran at 70 km/h instead of 55 and drank 24 liters per 100 km instead of 36. Mercedes-Benz had been testing a high-revving six, the OM 304, since 1941; the production engine was finished at Untertürkheim after the war, and the L 6600 heavy lorry reached the market in October 1950.

The bus came a month later: late-1940s O 5000 coachwork wrapped around the L 6600 driveline and six-speed gearbox, sold as the O 6600 and renamed O 304 in 1954. From March 1951 the same engine went in transversely at the rear of the O 6600 H, the first forward-control Mercedes-Benz bus with a rear engine — 1,935 of those were built to 1961, though 363 were trolleybuses carrying a traction motor instead. A multi-fuel OM 315 V was built to NATO requirements for the military LG 315, and a pressure-charged OM 315 A reached 180 PS. Production ran to 1979 and 40,207 engines.