The EMD SD89MAC is a 4,500 horsepower C-C diesel-electric locomotive produced by General Motors Electro-Motive Division. Along with the SD80MAC

EMD SD80MAC

The SD80MAC is a 5000 horsepower C-C diesel-electric locomotive. The SD80MAC uses a 20 cylinder version of EMD's 710G prime mover, and is the first diesel locomotive to utilize a 20 cylinder engine since the SD45/ SD45-2...

 and SD90MAC

EMD SD90MAC

The EMD SD90MAC is a C-C diesel-electric hood unit locomotive produced by General Motors Electro-Motive Division. It is, with the SD80MAC, one of the largest single-engined locomotives produced by that company, surpassed only by the dual-engined DD series...

, the SD89MAC is one of the largest single-engine locomotives produced by EMD, surpassed only by the dual-engined DD series. The SD89MAC features radial steering trucks and an isolated cab

Cab (locomotive)

The cab, crew compartment or driver's compartment of a locomotive is the part of the locomotive housing the train driver or engineer, the fireman or driver's assistant , and the controls necessary for the locomotive's operation....

 which is mounted on shock absorbers to reduce vibration. The SD89MAC uses AC traction motor

Traction motor

Traction motor refers to an electric motor providing the primary rotational torque of a machine, usually for conversion into linear motion ....

 technology. Like the SD90MAC, it is a hood unit

Hood unit

A hood unit, in railroad terminology, is a body style for diesel and electric locomotives. On a hood unit, the body of the locomotive is less than full-width for most of the locomotive's length, with walkways on the outside of the locomotive. In contrast, a cab unit has a full-width carbody for...

fitted with a safety cab and has an enlarged radiator section, nearly the entire width of the locomotive, which makes it easy to spot.

History

The SD89MAC was intended to be less-powerful version of the SD90MAC, and eventual successor to the SD70 series. A single prototype was built, but generated no orders.