The EMD F9 was a 1,750 horsepower (1,300 kW) Diesel-electric locomotive produced between February 1953 and May 1960 by the Electro-Motive Division of General Motors (EMD) and General Motors Diesel (GMD). It succeeded the F7 model in GM-EMD's F-unit sequence. Final assembly was at GM-EMD's La Grange, Illinois plant. The F9 was also built in Canada by General Motors Diesel at their London, Ontario plant. A total of 100 cab-equipped lead A units and 154 cabless booster B units were built. The F9 was the fifth model in GM-EMD's highly successful "F" series of cab unit diesel locomotives. A F9 can be distinguished reliably from a late F7 only by the addition of an extra filter grille ahead of the front porthole on the side panels on A units. Internally, the use of an 567C prime mover increased power to 1,750 hp from the F7's 1,500 hp. By the time cab units such as the F9 were built, railroads were turning to the road switcher-style of locomotive, and the F9 was succeeded in most part by the EMD GP9.