The EMD SW8 was built just prior to the end of production on the SW7. Ironically, while the SW8 was the latest version in EMD's switcher line at the time it was less powerful than the SW7. However, it did feature an updated version of EMD's model 567 prime mover although outwardly it remained virtually identical to its early predecessor and practically the same length. The SW8 sold relatively well (although not as well as either the SW1 or SW7) to both large and small railroads, as well several industries. With the Electro-Motive Division's opening of its Canadian subsidiary, General Motors Diesel in Ontario, it also sold a handful of SW8s to northern roads. The resiliency of EMC/EMD's SW series is something to behold, as the SW8, like nearly all its counterpart models, continues to be operated in all types of settings from shortline and industrial applications to excursion trains.
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The EMD SW8 began production in September, 1950, shortly before the last SW7s were built in January, 1951. Outwardly, the SW8 was, again, not drastically different from the SW7 or even the NW2. It featured General Motors' model D37 traction motors which could produce a modest 36,000 pounds of starting tractive effort (57,000 pounds continuous) and overall weighed just 115-tons (which was actually nine tons lighter than the SW7). The SW8's carbody, as with earlier models, featured the now classic tapered hood in front of the cab although one visual difference was that it included only one centered exhaust stack (the SW7, NW2, SW1, and later models almost always had two).
Internally, the EMD SW8's one noticeable difference was its model 567B prime mover, then the newest engine EMD had developed. The eight-cylinder engine could produce 800 horsepower, which was a step down from the 1,200-horsepower SW7. Still, while the SW8 had fewer sales than its predecessor it attracted many different railroads from Class Is to shortlines and industries. Some buyers ranged from large systems like the Wabash, Southern Pacific, New York Central, and Rock Island to small lines like the Roscoe, Snyder & Pacific Railway, Wichita Falls & Southern Railroad, and Colorado & Wyoming Railway.
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Additionally, industries like Wheeling Steel (who bought numerous examples of EMD's various switchers), Pittsburgh Coke & Chemical Company, and Columbia Iron & Steel all purchased the SW8. Again, these wide range of buyers can be explained by the intended use EMD designed the locomotive which included yard duty, light branch line work, and shuffling cars through industrial settings. The SW8 had a four-year production run and when the last model was outshopped in January, 1951 EMD had built some 374 units, which included those constructed by General Motors Diesel of Ontario, Canada (which had been established only in 1949) and 12 sets of cow-calf TR6s. Buyers from GMD included Algoma Central, Algoma Steel, Canada & Gulf Terminal, Canadian National, Canadian Pacific, Dominion Foundries & Steel Company, Dominion Iron & Steel, Essex Terminal Railway, Steel Company of Canada, and Wabash again (for use on its line between Detroit and Niagara Falls in Ontario).
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As for the cow/calf TR6 just twelve sets were built; one demonstrator (that went to Southern Pacific), eight for the Oliver Iron Mining Company, and three more to SP. Once again, the reliability and versatility of the SW series has been well represented in the SW8 as numerous models continue to perform admirably in all types of settings. Places you can still find SW8s in service include the North Shore Railroad, Strasburg, Larrys Truck & Electric, Reading & Northern, Madison Railroad, Moldok, Berkshire Scenic Railway, Stelco Inc., Maryland & Delaware Railroad, Mansbach Metal Company, Johnson County Airport Commission, Relco Locomotives, Colorado & Wyoming Railway, and the Chicago Terminal. For technical data regarding the EMD SW8 please click here. Also, for information about EMD's various switchers please refer to the chart below.
Electro-Motive Division Switchers
| Model Type | Units Built | Date Built | Horsepower | NW2 | 1,145 | 1939-1949 | 1,000 | NW3 | 7 | 1939-1942 | 1,000 | NW5 | 13 | 1946-1947 | 1,000 |
|---|---|---|---|
| SW1 | 661 | 1939-1953 | 600 | RS1325 | 2 | 1960 | 1,325 | SW600 | 15 | 1954-1962 | 600 | SW7 | 489 | 1949-1951 | 1,200 | SW8 | 374 | 1950-1954 | 800 | SW9 | 815 | 1950-1953 | 1,200 | SW900 | 371 | 1953-1969 | 900 | SW1000 | 119 | 1966-1972 | 1,000 | SW1001 | 230 | 1968-1986 | 1,000 | SW1200 | 1,056 | 1954-1966 | 1,200 | SW1500 | 808 | 1966-1974 | 1,500 | SW1504 | 60 | 1973 | 1,500 | MP15/DC/AC/T | 640 | 1974-1987 | 1,500 |
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For more reading about EMD SW8s and related diesel locomotives built by General Motors consider Mike Schafer’s Vintage Diesel Locomotives which looks at virtually all of the classic builders and models from Alco PAs to early EMD Geeps. If you’re interested in classic EMDs, or diesels in general, this book gives an excellent general history of both. You might want to also consider the book EMD Locomotives from author Brian Solomon. Solomon's book highlights the history of EMD from its earliest beginnings in the 1920s, to its phenomenal successes in the mid-20th century, and finally its decline into second spot behind General Electric in the late 20th century and eventual sale by General Motors in 2005. The book features 176 pages of EMD history and is filled with excellent photography and illustrations. If you're interested in perhaps purchasing either (or both) of these books please visit the links below which will take you to ordering information through Amazon.com, the trusted online shopping network.
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