# EMD SW1200

An EMD SW1200 is a four-axle diesel switcher locomotive built by General Motors Electro-Motive Division between January 1954 and May 1966. Power is provided by an EMD 567C 12-cylinder engine, which generates 1,200 horsepower (890 kW). Additional SW1200 production was completed by General Motors Diesel in Ontario, Canada, between September 1955 and June 1964.
737 examples of this locomotive model were built for U.S. railroads, 287 were built for Canadian railroads, four were built for Brazilian railroads, 25 were built for a Chilean industrial firm, and three were built for the Panama Canal Railway.

## Design and production

The SW1200 was the third model of 1,200 hp SW series switchers built by EMD. It was a successor to the SW7 and SW9. Compared to its direct predecessor, the SW9, the SW1200 differed in that it used the improved and more reliable 567C engine, compared to the SW9's 567B engine. Late SW1200s built in 1966 were instead built with the 567E 12-cylinder engine. Most of the locomotive's external features were unchanged from the SW9, making distinguishing between the two models difficult.
SW1200 production began in January 1954, immediately after SW9 production came to an end the previous month. Production continued for 12 years until the last SW1200 left EMD's manufacturing facility in May 1966.
Like many EMD products, customers could customize their SW1200 orders. Several options were available, including Flexicoil trucks. A few units were built with dynamic brakes, featuring a large square box with a fan on top of the hood, right in front of the cab.

## Variants

A cow–calf variation, the TR12, was cataloged, but none were built.
An SW1200RS (RS for road switcher) is a variation of the standard SW1200 that features large front and rear (on some units) numberboard housings, EMD Flexicoil B-B trucks, and larger fuel tanks for road switcher service. The majority of the Canadian National and Canadian Pacific SW1200 fleets were purchased as SW1200RS units. SW1200RS units were produced near the end of SW1200 production in the mid-1960s.

## Original buyers
### Units built by Electro-Motive Division, United States

| Railroad | Quantity | Road numbers | Notes |
| Aliquippa and Southern Railroad | 13 | 1201–1213 | |
| Amapa Railway | 4 | 1–4 | Brazil |
| Ashley, Drew and Northern Railway | 2 | 176, 178 | |
| Atchison, Topeka and Santa Fe Railway | 3 | 2439–2441 | |
| Baltimore and Ohio Railroad | 8 | 9614–9621 | |
| Bauxite and Northern Railway | 1 | 11 | |
| Bellefonte Central Railroad | 1 | 5624 | |
| Belt Railway of Chicago | 3 | 524–526 | |
| Birmingham Southern Railroad | 2 | 200–201 | |
| Chicago and Illinois Midland Railroad | 6 | 18–23 | |
| Chicago and North Western Railway | 12 | 310–321 | Acquired by EJ&E Railway then to Gary Railway (315 and 316 not part of GRW fleet) |
| Chicago, Burlington and Quincy Railroad | 22 | 9271–9292 | to Burlington Northern 229–250 |
| Chicago, Milwaukee, St. Paul and Pacific Railroad ("Milwaukee Road") | 48 | 1637–1642, 2020–2061 | Renumbered 600–619, 625–652 (not in order) |
| Chicago, Rock Island and Pacific Railroad | 17 | 920–936 | |
| Chile Exploration Company | 25 | 911–935 | Chile |
| Colorado and Southern Railway | 5 | 156–160 | to Burlington Northern Same |
| Commonwealth Edison | 1 | 16 | |
| Conemaugh and Black Lick Railroad | 2 | 120–121 | |
| Coos Bay Lumber Company | 3 | 1201–1203 | Built with dynamic brakes. |
| Cuyahoga Valley Railway | 7 | 1280–1286 | |
| Delaware, Lackawanna and Western Railroad | 8 | 561–568 | to Erie Lackawanna 456–463 |
| Denver and Rio Grande Western Railroad | 10 | 130–139 | |
| De Queen and Eastern Railroad | 1 | D-5 | |
| Elgin, Joliet and Eastern Railway | 8 | 300–307 | 300–301, 303–305 and 307 are now part of the Gary Railway Co. fleet per the 2009 CN acquisition of EJ&E Railway. 306 to LTEX 306 |
| Florida East Coast Railway | 7 | 229–235 | |
| Fort Worth and Denver Railway | 4 | 607–610 | to Burlington Northern Same |
| Grand Trunk Western Railroad | 18 | 1269–1270, 1505–1508, 1511–1519, 7017–7019 | |
| Great Lakes Steel Corporation | 16 | 16, 39–53 | |
| Great Northern Railway | 6 | 29–33, 100 | 100 Rebuilt from EMC NC to Burlington Northern 162–166 |
| Houston Belt and Terminal Railway | 5 | 33–37 | |
| Illinois Terminal Railroad | 12 | 775–786 | |
| Inland Steel Company | 27 | 88–114 | |
| Kansas City Terminal Railway | 10 | 70–79 | |
| Lake Superior Terminal and Transfer | 1 | 105 | |
| Louisville and Nashville Railroad | 4 | 2297–2300 | |
| Midland Electric Coal Company | 1 | 1201 | |
| Minneapolis, Northfield and Southern Railway | 6 | 30–35 | to Soo Line |
| Minneapolis, St. Paul and Sault Ste. Marie Railroad, ("Soo Line") | 8 | 321–328 | 321, 323 and 324 were acquired by EJ&E Ry then part of Gary Ry Co. One unit acquired by Tulsa-Sapulpa Union Railway, now in active service as its Number 108. |
| Soo Line (Wisconsin Central Railroad) | 8 | 2120–2127 | |
| Missouri Pacific Railroad | 116 | 1100–1166, 1175–1201, 1255–1259, 1263–1279 | Withdrawn in 1985 after the UP takeover. Sold to various owners or scrapped. |
| Missouri Pacific (Texas and Pacific Railway) | 20 | 1280–1299 | Withdrawn in 1985 after the UP takeover. Sold to various owners or scrapped. |
| Missouri–Kansas–Texas Railroad | 8 | 1–6, 43–44 | |
| New York, New Haven and Hartford Railroad | 20 | 640–659 | to Penn Central 9180–9199 and then Conrail 9363–9382 |
| New Orleans Public Belt Railroad | 2 | 71–72 | |
| Norfolk and Portsmouth Belt Line Railroad | 15 | 101–115 | |
| Northern Pacific Railway | 59 | 119–177 | to Burlington Northern 170–228 |
| Oliver Iron Mining Company | 9 | 940–948 | |
| Pacific Power and Light | 1 | 10 | |
| Panama Canal Railway | 3 | 661–663 | |
| Patapsco and Back Rivers Railroad | 10 | 125–134 | |
| Pennsylvania Railroad | 35 | 7900–7934 | To Penn Central |
| Peoria and Pekin Union Railway | 1 | 500 | |
| Philadelphia, Bethlehem and New England Railroad | 5 | 39–43 | |
| Point Comfort and Northern Railway | 1 | 4 | |
| Reading Company | 5 | 2715–2719 | Equipped with 930 Gal. Fuel tanks |
| Republic Steel Corporation | 2 | 362, 895 | |
| Reserve Mining Company | 1 | 1212 | |
| Richmond, Fredericksburg and Potomac Railroad | 5 | 81–85 | |
| River Terminal Railway | 2 | 63–64 | |
| Rockdale, Sandow and Southern Railroad | 1 | 8 | |
| Sandersville Railroad | 1 | 200 | renumbered 1200, upgraded to 12–645 spec |
| Simpson Logging Company | 2 | 1200–1201 | Built with Dynamic Brakes. |
| Southern Pacific Transportation Company | 27 | 1597–1623 | renumbered 2262–2288 |
| Southern Pacific (Texas and New Orleans Railroad) | 12 | 113–118, 123–128 | renumbered 2213–2223 |
| St. Louis Southwestern Railway ("Cotton Belt") | 17 | 1062–1073, 2289–2293 | 1062–1073 renumbered to 2250–2261 |
| Steelton and Highspire Railroad | 1 | 44 | |
| Terminal Railroad Association of St. Louis | 25 | 1219–1243 | |
| Tooele Valley Railway | 1 | 100 | |
| U.S. Steel | 2 | SX1–SX2 | |
| Wabash Railroad | 5 | 375–379 | |
| West Virginia Northern Railroad | 1 | 52 | Built with dynamic brakes. |
| Weyerhaeuser Timber Company | 1 | 304 | |
| Wheeling Steel | 7 | 1250, 1254–1259 | |
| Woodward Iron Company | 1 | 52 | |
| Total | 769 | | |

### Units built by General Motors Diesel, Canada

| Railroad | Quantity | Road numbers | Notes |
| Canadian Forest Products | 3 | 301–303 | Flexicoil trucks, built with dynamic brakes |
| Canadian National Railway | 208 | 1227–1268, 1271–1397, 1575–1597, 7020–7035 | 12/13/1500s have Flexicoil trucks and numberboards at both ends. Some units rebuilt to SW1200RMs |
| Canadian Pacific Railway | 72 | 8100–8171 | Flexicoil trucks, numberboards at front only |
| Dominion Foundries and Steel ("Dofasco") | 1 | 14 | |
| Essex Terminal Railway | 1 | 105 | |
| Quebec Iron and Titanium | 1 | 5 | Romaine River Ry |
| Roberval and Saguenay Railway | 1 | 23 | |
| Total | 287 | | |