OM501

The Actros program was set in motion in 1990 and began in earnest in 1992, and it replaced almost everything at once — cab, brakes, gearshift, electronics, engines. The OM 501 LA was its V6: 90° between the banks, one turbocharger for the whole engine, and the first Mercedes-Benz diesel to abandon the inline injection pump. Each cylinder got its own unit pump sitting on the crankcase over its own cam lobe, a solenoid valve setting timing and quantity, and injection pressure reaching 1,800 bar. Launch ratings ran from 313 to 428 PS.

It was engineered to run a million kilometers and it stayed in the range for fifteen years. Compression rose from 17.75:1 to 18.5:1 for Euro IV and V, peak firing pressure from 170 to 180 bar, and AdBlue SCR handled the rest. Beyond the Actros it went into Travego and Tourismo coaches and Setra chassis, while MTU sold an armored-vehicle version as the 6V199, used in Australian M113 rebuilds, the Fuchs 2 and the Piranha V. Mercedes-Benz retired the V6 from its trucks in favor of the inline OM 470 and OM 471 from 2011.