GP50 Diesel Locomotive

Prototype Information

The EMD GP50 is a 4-axle diesel road switcher locomotive built by General Motors Electro-Motive Division between 1980 and 1985. It is powered by a 16-cylinder EMD 645F3B diesel engine, which can produce between 3,500 and 3,600 hp.

A total of 278 examples of this locomotive were built. The GP50 retains the same overall length of 59 feet 2 inches as the other GP dash-2 series locomotives built in the same era. It utilized GM’s D87 traction motor enabling it to produce a starting tractive effort of 65,000 pounds, with a continuous rating of 62,400 pounds.

The most significant difference in the GP50 from earlier designs like the GP40 was upgraded components (like a turbocharger silencer and new type of blower housing) and increased horsepower. The locomotive also introduced a new “anti-wheel-slip” technology where the locomotive horsepower output was reduced if a wheel slip condition was introduced. It also included features already common on earlier models such as dynamic braking (a system for temporarily employing traction motors as generators and using the resulting electromotive force to slow the train), and an airtight hood that kept out dust, dirt and other particles from reaching internal components.