SW9

The Electromotive Division SW9 is a 4 axle, 1,200 HP diesel-electric locomotive built by EMD from 1950 to 1953. It uses a 12 cylinder 567B prime mover rated at 1,200 HP and rides on a pair of AAR type A switcher trucks. The SW9 was the last EMD switcher to use the 567B prime mover, which was water cooled. Newer units like the SW1200 use the 567C prime mover which is cooled by antifreeze. As a result, SW9's have to be kept running, stored inside or drained in order to keep from freezing in cold weather. 786 SW9's were built, with 29 additional units being built in Canada by GMD. While not as numerous as they once were, several SW9's continue to work for private owners, shortlines, and tourist railroads. The SW9 should not be confused with the later, 900 HP, 8 cylinder SW900.

EMD also built 10 sets of SW9's drawbarred to cabless SW9 units (called "calfs"), designated TR5's and nicknamed "Cow & Calf" sets (the SW9 cab unit being the "cow"). 8 sets went to Union Pacific, the remaining 2 went to the Union RR.

Back to EMD Freight Locomotives