Burlington Northern SD9 No. 6234.

(Keon McGarvey, CC BY-SA 4.0 <https://creativecommons.org/licenses/by-sa/4.0>, via Wikimedia Commons)



The EMD SD9 is a model of diesel locomotive built by General Motors Electro-Motive Division between January 1954 and June 1959. An EMD 567C 16-cylinder engine generated 1,750 horsepower (1.30 MW). Externally similar to its predecessor, the SD7, the SD9 was built with the improved and much more maintainable 567C engine.

Four hundred and seventy-one SD9s were built for American railroads, while a further 44 were produced for export.

Many SD9s both high and short-hood can still be found in service today on shortline railroads and industrial operators. Although most Class 1 roads stopped using these locomotives by the 1970s and 1980s, some remain in rebuilt form on some major Class I railroads, as switcher locomotives.



The SD9 was the second model of EMD's SD (special duty) line of locomotives, following the SD7. Just as the SD7 was a lengthened GP7 with two additional axles, the SD9 was a corresponding modification of the GP9. The additional axles in SD series locomotives provide more tractive effort and more even distribution of locomotive weight compared to the four axle GP series locomotives.

SD9s can be distinguished from the similar looking SD7s by observing the position of the classification lights on the ends of the locomotive, above the number board. The SD9's classification lights are on a small pod, canted outward, while the SD7's classification lights are closer to the centerline and flush with the hood.

The last phase of construction had a carbody similar to the SD18 and SD24, and used two 48-inch (1,219 mm) cooling fans instead of four 36-inch (914 mm) cooling fans.

EMD ended SD9 production in June 1959. It was succeeded by the SD18 which began production in 1960.



EMD produced a lightweight variant of the SD9, named the SD9s. This locomotive had its weight reduced for service on lighter tracks with modifications such as a smaller fuel tank.



See main article EMD SD9E

Between August 1970 and March 1980, the Southern Pacific Transportation Company had rebuilt 144 of their units into EMD SD9E diesel locomotives under their own rebuild program known as the General Rehabilitation and Improvement Program (G.R.I.P) and renumbered 142 of their rebuilt units as 4300-4441 and two additional rebuilt units being renumbered as 4450 and 4451, as well as reclassifying their 142 units as EF618E-1 and classified their two units No. 4450 and No. 4451 as EF618E-2, which had left six other SD9 locomotives that were not rebuilt.


Norfolk & Western SD9 No. 2349 mat the Mad River & NKP Railroad Museum in Bellevue, OH, July 30, 2014.

(jpmueller99 from Columbus, OH, USA, CC BY 2.0 <https://creativecommons.org/licenses/by/2.0>, via Wikimedia Commons)


Original buyers

Railroad Quantity Road numbers Notes
Electro-Motive Division (demonstrator) 1 5591 to Duluth, Missabe and Iron Range 110
Atlanta and St. Andrews Bay Railroad 3 503–505
Baltimore and Ohio Railroad 10 765–774
Chicago, Burlington and Quincy Railroad 80 325–374, 430–459 300s had steam generators. To Burlington Northern 6127-6206
Chicago, Burlington and Quincy Railroad (C&S) 23 820–842 To Burlington Northern 6215-62376234 preserved
Central of Georgia Railway 6 202–207
Chicago and Illinois Midland Railroad 5 50–54
Chicago and North Western Railway 14 1701–1710, 1721–1724 Fitted for Chicago commuter service
Chicago, Milwaukee, St. Paul and Pacific Railroad 14 2224–2237 Renumbered 530-543
Chile Exploration 5 901–905 Track gauge unknown
Duluth, Missabe and Iron Range Railroad 73 101–109, 111–174 129–130 had steam generators
Denver and Rio Grande Western Railroad 10 5305–5314
Elgin, Joliet and Eastern Railway 3 600–602
Great Northern Railway 27 573–599 To Burlington Northern 6100-6126
Korail (Korea) 29 101–129 Later renumbered 5001-5029
New York, Chicago and St. Louis Railroad (“Nickel Plate Road”) 20 340–359
Orinoco Mining (Venezuela) 10 1011–1020
Pennsylvania Railroad 25 7600–7624
Reserve Mining 6 1220–1225 To Escanaba and Lake Superior Railroad
Soo Line (Wisconsin Central Railroad) 1 2381
Southern Pacific Company 150 5340–5444, 5449–5493 5340–5391 had steam generators
Total 515

AERC 5399 in PNWR's main dispatch yard in Albany, Oregon on April 28th, 2022.

AERC 5399 is an EMD SD9 originally delivered to the Southern Pacific Railroad in February 1955.

Now, it is used in revenue and excursion service by the Albany and Eastern Railroad, April 28, 2022.

(N9002U, CC BY-SA 4.0 <https://creativecommons.org/licenses/by-sa/4.0>, via Wikimedia Commons)



Some SD9 locomotives can be found in museums and on tourist lines, and at least two are in service on a working railroad:

  • Dakota Southern Railway used SD9 No. 506 and SD9E No. 4427 in revenue freight service.
  • BNSF 6125 was donated to the Inland Northwest Rail Museum at Reardan, WA in 2020. This unit was originally built for the Great Northern Railway as GN 598 and was incorporated in the formation of the Burlington Northern Railroad in 1970. It became part of BNSF after the merger of the Burlington Northern and Santa Fe Railroads in 1995. The same museum would later acquire former GN 599 from the City of Skykomish, Washington in early 2023 and will be cosmetically restored with its mechanical parts used for 598's restoration.
  • The Columbia Basin Railroad In Eastern Washington State owns 5 ex-BNSF and Montana Rail Link SD9s that are actively used in both road and switching service.
  • The Escanaba and Lake Superior Railroad uses No. 1223, formerly of Reserve Mining, in regular service around Escanaba, Michigan; other SD9s owned by the railroad are as of 2016 in a "deadline" in Wells, Michigan.
  • Colorado & Southern 839, later Burlington Northern 6234, was donated by successor Burlington Northern Santa Fe Corp. to the Minnesota Transportation Museum. It now operates on the museum's Osceola and St Croix Valley Railway. 6234 is an example of the last variation of SD9 locomotives produced, which used the SD18 carbody.
  • The Nevada Northern Railway uses No. 204, ex-SP SD9E No. 4426 to occasionally to pull their passenger trains.
    Southern Pacific 4404 is preserved at WRIX/Western Rail INC.
  • Milwaukee Road 532, rebuilt by the Milwaukee into an 'SD10', lives at the Whitewater Valley Railroad. It was originally their 2235.
  • Nickel Plate Road 349 is preserved at the Mad River & Nickel Plate Railroad Museum. It was retired as Norfolk Southern No. 52, and was donated to the museum in December 2010. It has been restored to its Norfolk & Western appearance.
  • Nickel Plate Road 358 is preserved at the Fort Wayne Railroad Historical Society. Undergoing full restoration into NKP appearance.
  • The Portland and Western Railroad uses two SD9s for switching and industry service. PNWR 1852 operates out of their Albany, OR Burlington Northern yard and PNWR 1854 is assigned to the rock train, both Ex-SP Heritage. Both locomotives are scheduled to be scrapped by parent company GWI as part of a fine resolution agreement with the EPA.
  • The Oregon Coast Scenic Railroad has an ex-BN SD9 6139 in operating condition and is used as a backup locomotive for its excursions.
  • The Western Rail Inc. owns 3 SD9m (SD9 rebuild) units. 13, 50, & 1886. 13 & 50 are Ex-Norfolk Southern, Exx-Norfolk & Western, née Nickel Plate Road. 1886 is Ex-Norfolk Southern, Exx-Southern, née Central of Georgia.
  • BNSF No. 1550 has been donated to the Lake Superior Railroad Museum.
  • An ex-Central of Georgia SD9, Black River & Western Railroad 9581, is currently on lease to Kinder-Morgan Newport News for yard duty.
  • The Albany & Eastern Railroad (AERC) has 1 SD9E in Black Widow paint, AERC/LLW 5399, It is used for both Passenger and Freight service in Lebanon, OR.
  • KORAIL 5025 is only preserved SD9 in Korea, plinthed in front of Daejeon MPD, Korea, along single G12 4102. Both engines worked for construction of KTX Gyeongbu section as departmental vehicles upon retirement of KORAIL.
  • The Niles Canyon Railway owns one Ex-Southern Pacific SD9 No. 5472. It was built in 1956 and had a restoration to operational condition in 2005.


Chicago & Illinois Midland Nos. 60, an EMD SD18, leading Nos. 50, and 52, both EMD SD9s at the engine house at Springfield, IL on May 7, 1966.

(Roger Puta, courtesy Marty Bernard, railfan 44, Public domain, via Wikimedia Commons)



Type and origin
Power type: Diesel-electric
Builder: General Motors Electro-Motive Division (EMD)
Model: SD9
Build date: January 1954 – June 1959
Total produced: 515
​• AAR C-C
Gauge: 4 ft 8+1⁄2 in (1,435 mm) standard gauge
Wheel diameter: 40 in (1,016 mm)
Wheelbase: 48 ft 7 in (14.8 m)
Length: 60 ft 8.5 in (18.5 m)
Fuel capacity: 1,200 or 2,400 US gal (4,500 or 9,100 L; 1,000 or 2,000 imp gal)
Lubricant capacity: 200 US gal (757 L)
Sandbox capacity: 50 cu ft (1.4 m3)
Prime mover: EMD 567C
Engine type: V16 diesel
Boiler: Vapor-Clarkson Steam Boiler OK4625
Cylinders: 16
Performance figures
Power output: 1,750 hp (1.30 MW)
Disposition: Many have been rebuilt, and are still in service.