The Detroit Diesel Series 50 is a straight-4 diesel engine, that was introduced in 1993 by Detroit Diesel. The Series 50 was built off of the existing block of its sister engine the Series 60 which itself was initially designed by Detroit Diesel The heads were cast by John Deere at one time. Deere is known for quality engines used in highway vehicle applications.

The Series 50 engine was used as a major bus engine in the United States and Canada. The power plant is offered for several applications: trucks, buses, motor homes, construction & industrial equipment, and military vehicles. It is unusual to find a straight-4 engine being used in heavy duty buses, which traditionally use a straight-6, V-6 or V-8 diesel engine.

In 2000, in order to better respond to the tougher EPA emisisons stardards, Detroit Diesel announced revisions of the Series 50 for diesel appications. The changes included the addition of an exhaust gas recirculation (EGR) system, and a variable geometry turbocharger system to improve torque.

The Detroit Diesel Series 50 runs on diesel and the Series 50G on compressed natural gas (CNG). A few thousand units engines are now in the buses on the streets of major cities such as New York City and Philadelphia.

In September 2004 Detroit Diesel ceased production of the Series 50 heavy duty diesel engine for on highway applications. It is still available for off-road applications.

Features Edit

  • 8.5 liter
  • Power ratings ranging from 250 to 320 horsepower (187 to 239 kW)
  • Supports the DDECIII and DDECIV
  • Since 2001 the engines included an EGR device.
  • Twin balance shafts

Detroit Diesel
Current Products DD15 - Series 60 - MBE 900 - MBE 4000
Former Products Series 40 - Series 50 - Series 53 - Series 71 - Series 92