The EMD MP15, sometimes referenced as MP15DC, is a 1,500 hp (1,119 kW) diesel–electric road switcher locomotive model produced by General Motors' Electro-Motive Division between 1974 and 1980.

In 1973 60 special order Mexico-only SW1504s were built on a slightly longer frame, allowing EMD's standard Blomberg B trucks, with a 108 in (2,743 mm) wheelbase, to be used.

The alternator-rectifier combination is more reliable than a generator, and this equipment became the standard for new diesel-electric locomotive designs.

Side intakes allowed the unit to take in cooler air, and the electric fans improved a serious reliability issue found in its earlier DC sisters.

Introduced in the SW1500, this was a 2-stroke, 45-degree V type, with a 9 1⁄16-inch bore by 10-inch stroke, giving 645 cubic inches displacement per cylinder.