The EMD F9 is a 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 101 cab-equipped lead A units and 156 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.
An 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 from the F7's .
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.
Engine and powertrain
The F9 used a 16-cylinder 567C series Diesel engine developing at 800 rpm. The 567 was designed specifically for locomotive applications, being a 45 degree V-type two-stroke design, with displacement per cylinder, for a total of . A D.C. generator powered four D37 traction motors, two on each Blomberg B truck. EMD has built all of its major components since 1939.