The GP40 is a 4-axle diesel-electric locomotive built by General Motors' Electro-Motive Division between November 1965 and December 1971. It has an EMD 645E3 16-cylinder engine generating 3,000 hp (2,240 kW). On January 1, 1972, the GP40 was discontinued and replaced by the GP40-2, which has a modular electrical system and a few minor exterior changes.