EMD "SW1" Locomotives: Specs, Roster, Photos

The EMD SW1 was the second model produced in the SW series and the last built by the Electro-Motive Corporation before it became an official division of General Motors. As with the NW2, cataloged during the same time period, the SW1 was quite popular, witnessing well over 600 sales before production had ended.  While it never sold as well as the NW2, the SW catalog went on to become EMD's primary switcher line.  Future models like the SW7, SW8, SW9, SW1200, and SW1500 all saw strong sales.  Today, the SW1, as with the NW2, continues to soldier on in all types of applications from regular freight service on short lines to industrial settings.  In addition, you can find them excursions and tourist trains. Even the very first SW1, built in early 1938, remains preserved at the California State Railroad Museum in Sacramento. 

As of today, there are more than two dozen SW1's officially preserved from Monon Railroad DS-50, the company's very first diesel it ever acquired in 1942, at the Indiana Transportation Museum, to Lehigh Valley #114 found in service on tourist line Wilmington & Western (as #114).

Milwaukee SW1 #872 is tied down in East Moline, Illinois during April of 1980. Like the DRI&NW switcher in the below photo, the Milwaukee helped serve remaining customers here after the Rock Island closure. Rob Kitchen photo.

While General Motors' Electro-Motive Division (EMD) often gets the credit for cataloging highly successful first generation switcher models like the NW2, SW1, SW9, SW1200, and numerous others the history behind these locomotives is sometimes forgotten. It actually all began with the Electro-Motive Corporation, before it was a division of GM. During the mid to latter 1930s the company began marketing various switcher designs meant for certain tasks like the SC, NW, SW, and NC. Most of EMC's designations of its switchers simply referred to how their frames were constructed and their horsepower rating. In the case of the SW this meant six hundred horsepower built with a welded frame.  

The corresponding numbers that followed in later models simply regarded their place in the series. Of course, under GM, ownership some of these designations changed but in general stayed the same. The EMD SW1 was the second model in the series and while it also featured a 600 horsepower prime mover (using the new GM six-cylinder model 567, and later the 567A), the "SW" designation of future models was in name only (the "S" would come to denote "switcher"), as just the later SW600 featured 600 hp (most were more powerful). The unit retained EMC's signature short carbody of just 44-feet with tapering just short of the cab.

Boston & Maine SW1 #1119 (built for the railroad in 1953) lays over at Lawrence, Massachusetts on February 8, 1970. Roger Puta photo.

Once again, as with the NW2 released that year, the SW1 featured GM's own model D37 traction motors and not those built by General Electric (which was used on early EMC switchers). Even at the early date GE was now a competitor to EMD through its affiliation with the American Locomotive Company (Alco). Up to that time, the SW1 offered some of the highest tractive effort for an EMD/EMC switcher; 49,500 pounds starting effort and 34,000 pounds continuous. Interestingly, the design was even lighter than the NW2, at just a paltry 99 tons! One noticeable difference of the SW1s compared to similar models was its short, "porches" at the front and aft ends of the locomotive.

Incredibly, this SW1 made it into NS paint; the switcher is seen here red-flagged at the Roanoke Yard in Virginia during the summer of 1988. It began its career on the Southern in the 1940s. Wade Massie photo.

The model was one of the few EMD switcher locomotives to receive a new prime mover while in production. After World War II the SW1 was reequipped with EMD's updated 567A prime mover, which still produced 600 horsepower. During this time the model also featured a slight update to its carbody. The original switcher was designed with a double-taper near the cab while the updated version featured just a single taper. Other new additions included a better conical, exhaust stack (which became standard on all future EMD switcher locomotives) for better crew visibility, rectangular instead of curved windshields, and a two-beam headlight (the original version included simply a single light).

Penn Central SW1 #8441, a former New York Central unit, pulls Flexivans at the road's terminal in Indianapolis, Indiana on March 4, 1970. Roger Puta photo.

EMD SW1 Production Roster

Owner Road Number(s) Quantity Date Built
Allegheny & South Side Railroad10111951
Allis-Chalmers Manufacturing Company811947
Angelina & Neches River Railroad1011947
Atlantic & East Carolina Railway911947
Baltimore & Ohio Chicago Terminal (B&OCT)216-22161942
Boston & Maine1109-1132241939-1953
Broward County Port Authority40011943
Buffalo Creek Railroad4211940
Burlington9136-9153181939-1941
Canton Railroad21-2551941-1949
Central Indiana Railway111949
Central Of Georgia1-3, 741939-1941
Central Railroad Of New Jersey (CNJ)1009-101241939-1942
Chattanooga Traction Company411947
Chicago & Eastern Illinois95-9951941-1942
Chicago & North Western1207-1215, 1268-1279, 1271 (2nd)221942-1953
Chicago Distric Electric Generating Company3-421947-1948
Chicago, St. Paul, Minneapolis & Omaha (C&NW)5511940
Chicago River & Indiana Railroad (NYC)615-62171950
Chicago Short Line Railway200-20121942-1949
Cleveland Quarries Company211953
Commonwealth Edison10-1561941-1950
Conemaugh & Black Lick Railroad60-6561949-1950
Detroit Edison Company210-21231949-1950
Detroit, Toledo & Ironton900-90121941
Donner-Hanna Coke Corporation111941
Electro-Motive (Demo)152, 700, 755, 802-806, 905-906, 911101938-1951
Elgin, Joliet & Eastern220-246271940-1941
Erie Railroad36011948
Fort Worth & Denver City Railway (CB&Q)602, 60421939-1942
Fort Worth Belt Railway111939
Galveston Wharves201-20551949-1951
Garden City Western Railway20111952
Georgia & Florida Railway70-7231950
Georgia Marble Company111947
Granite City Steel Works (U.S. Steel)600-60121951
Great Lakes Steel Corporation11-18, 22 30-31, 33-36, 38151939-1953
Great Northern80-83, 5101-510591939-1950
Great Western Railway6111952
Hanna Furnance Company14-1631948-1953
Houston Belt & Terminal Railway1011940
Illinois Central9014-9032191939-1951
Inland Steel Company51, 54, 57, 70-73, 76-81131939-1951
International-Great Northern Railroad (MP)9200-900561939-1941
Lackawanna427-437111940
Lehigh Portland Cement Company511953
Lehigh Valley112-115, 118-11961939-1950
Louisiana Midland Railway1111952
Louisville & Nashville11-1551939-1941
Manufacturers' Junction Railway6-721946-1947
Maryland & Pennsylvania (Ma & Pa)7011946
Mathieson Chemical Company1-221947-1949
McLouth Steel Corporation3-531950-1953
Memphis Union Station1011942
Metropolitan Sanitary District Of Greater Chicago1-331952
Milwaukee Road1610-1634251939-1941
Missouri Pacific9004-9006, 901141939-1941
Monon Railroad5-6, 50, 105-10651942-1950
Nashville, Chattanooga & St. Louis1511941
New York Central574-599, 600-654, 600-614 (2nd)981939-1950
Pennsylvania5910, 5944-5953, 5987-5999, 9200-9203, 9104-9105, 9137-9154, 9396- 9428811942-1949
Pere Marquette10-1121939-1942
Phelps Dodge CorporationA11939
Philadelphia, Bethlehem & New England Railroad212-218, 220-22191940-1942
Portland Traction Company100, 20021952-1953
Public Service Company Of Northern Illinois9-1131950-1952
Reading16-18, 23-2451939-1941
Richmond Terminal111939
Republic Steel Corporation50-54, 300-306, 340-341, 352, 370-372, 890-891, 893- 894221939-1952
Rock Island529-546181942-1949
Roscoe, Snyder & Pacific Railway10011949
Sahara Coal CompanyNo Number11953
Seaboard Air Line120011939
Scullin Steel Company611951
St. Johns River Terminal Company (Southern)856511940
St. Joseph Belt Railway1211947
St. Joseph Terminal Railway1-221950
Soo Line32011939
Southern Pacific1000, 1004-1016141939-1941
Southern Railway2002-2004, 2007-201181940-1947
Tennessee Coal & Iron Railroad1000-100341948
Terminal Railroad Association Of St. Louis (TRRA)501-50881940-1947
Texas & New Orleans (SP)1111941
Union Railroad455-476221949-1950
U.S. Army7001-700441942
Wabash Railroad101-111111939-1949
Warner Sand & Gravel Company1511953
Western Pacific501-50331939
Wheeling Steel Corporation1001-100441946-1948


Davenport, Rock Island & Northwestern SW1 #871 and a transfer caboose are tied up at the depot in East Moline, Illinois during April of 1980. The author notes that after the Rock Island shutdown the DRI&NW began serving remaining customers here. Rob Kitchen photo.

Production of the EMD SW1 ran between the early winter of 1939 and November, 1953. Due to their flexibility, reliability, and a cheap price tag numerous Class Is and shortlines purchased the model with some 661 in total built. Just as with many other models, it also found a lot of interest with industries (like Wheeling Steel, Warner Sand and Gravel, Republic Steel, and others) and even the U.S. Army bought four models. Two years after the model was developed, EMC and the Winton Engine Company became an official division of General Motors on January 1, 1941. Today, just as with the NW2, the EMD SW1 has stood the test of time and remains in operation in several different applications from short lines to excursion trains. 




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Header Photo: Drew Jacksich




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