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The "SW8": An Early 8-Cylinder Switcher

Last revised: December 19, 2024

By: Adam Burns

During the era of Electro-Motive's 567 prime mover the builder manufactured numerous switchers in a variety of horsepower ratings.

Over time, the more powerful models in the 1,000-1,500 horsepower range witnessed the highest sales although EMD's product was so popular at the time even its lighter switchers enjoyed success.

The SW8 was once such example that saw more than 300 manufactured in the United States and Canada between 1950-1954.

Once again, interest for the model varied from major Class I's to private industries and short lines.  Even the U.S. Army acquired 41 examples.

The resiliency of the SW series is something to behold as SW8's can still be found in operation throughout North America.  It can be found in service ranging from short lines and industrial settings to pulling excursion trains. 

Photos

Rock Island SW8 #830 lays over at Hodges, Texas on January 29, 1984. At the time of this photo the locomotive was en route from El Reno, Oklahoma to the former Biddle Yard at Little Rock, Arkansas where it handled remaining clean up operations on the old Southern Division. Mike Bledsoe photo. American-Rails.com collection.

History and Background

The SW8 began production in September, 1950 when Wabash #120-121 rolled out of the La Grange facility. 

In addition, with Electro-Motive's Canadian subsidiary (General Motors Diesel) opening its doors in London, Ontario during 1949 the new builder also began manufacturing the switcher.

Its first included four units for Canadian Pacific (6700-6704) that were completed in November, 1950.

Outwardly, the SW8 was not drastically different from the SW7, or even the NW2, sporting EMD's classic tapered hood near the cab.  However, one external difference was a single, centered exhaust stack instead of two, the result of the switcher's 8-cylinder power plant.  

As Bob Hayden notes in his book, "Diesel Locomotives Cyclopedia: Volume 2," the lighter powered SW8, SW900, SW900M, and SW600 were virtually identical.

Jerry Pinkepank goes on to state in his book, "Diesel Spotter's Guide," as all of these models used the same carbody the only way to tell the SW8 apart from the others was the louvers; it featured six in the battery box behind the cab while the others had only five.

Internally, the SW8 sported the 8-cylinder, 567B prime mover that could produce 800 horsepower.   While this rating was similar to other switchers in its class, which ranged from 600-900 horsepower, interestingly it was far less than the 1,200 horsepower SW7.

Electro-Motive's model classification system for switchers is difficult to follow as the meaning given to the letters and numbers were changed more than once.

Erie Lackawanna SW8 #365, still in its Delaware, Lackawanna & Western markings (built as #505), lays over at the former DL&W roundhouse and shops in Scranton, Pennsylvania during the early 1960s. American-Rails.com collection.

While several well known lines purchased the SW8, such as New York Central, Wabash, Lehigh Valley, and Boston & Maine several private industries also acquired the locomotive. 

Names here included Wheeling Steel (who bought numerous examples of EMD's various switchers), Pittsburgh Coke & Chemical Company, and Columbia Iron & Steel.

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.

Data Sheet

Production Rosters

EMD

(Total Built = 302)

*  Became Illinois Terminal #725.  Sold as order number 6285.

**   Became Georgia Northern Railway #801.

*** Became Cuyahoga Valley Railway #855.  Sold as order number 4314.

Rebuilds

(Total Built = 7)

SW8's completed from trade-in units, reusing the same serials as their predecessors.

GMD

(Total Built = 65)

Sources

• Foster, Gerald. A Field Guide To Trains. New York: Houghton Mifflin, 1996.

• Hayden, Bob. Diesel Locomotives: Cyclopedia, Volume 2 (Model Railroader). Milwaukee: Kalmbach Publishing Company, 1980.

• Marre, Louis A. Diesel Locomotives: The First 50 Years, A Guide To Diesels Built Before 1972.  Milwaukee: Kalmbach Publishing Company, 1995.

• Pinkepank, Jerry A. Diesel Spotter's Guide.  Milwaukee: Kalmbach Publishing Company, 1967.

• Solomon, Brian.  EMD Locomotives.  Minneapolis: MBI Publishing Company, 2006.

In Canada, these companies included Dominion Foundries & Steel, Algoma Steel, Dominion Iron & Steel, and the Steel Company Of Canada (Stelco).

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.