OM355

By 1967 the loosening of the Seebohm weight rules and the steady rise in what hauliers expected of a heavy truck had left the OM 346 short. Rather than start again, Daimler-Benz lengthened the stroke from 140 to 150 mm, took the six to 11.6 liters and renamed it. As the OM 355 it made 230 PS at 2,200 rpm, and 240 PS from 1969, in the L 1623 and L 1624; a turbocharged OM 355 A gave 280 PS in the L 1928. In the O 302 coach it was the largest of four engines offered and the obvious choice for the twelve-meter car.

In Europe its time was brief — the V-engines of the 400 series displaced it during the 1970s. Everywhere else it kept going. The short-bonneted Kurzhauber trucks were exported until 1994 with this engine beneath them, naturally aspirated in the 1924 or turbocharged in the 1928. Brazil took to it particularly: from 1988 a turbocharged and intercooled OM 355 LA was built there and nowhere else, rated at 340 PS — a figure nobody had in mind when the cylinder spacing was settled back in 1956.