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DGVR40 Staunton WJGrimes.JPG
Type and origin
Power typeDiesel-electric
BuilderGeneral Motors Electro-Motive Division (EMD)
General Motors Diesel (GMD)
Build date1954 – 1963
Total produced4,092 (and 165 B units)
Gauge4 ft 8+12 in (1,435 mm) standard gauge
5 ft 3 in (1,600 mm) (Brazil)
TrucksEMD Blomberg B (Flexicoil on some CN units)
Wheel diameter40 in (1.016 m)
Minimum curve21° (273 ft (83.21 m) radius)
Wheelbase40 ft (12.19 m)
Length56 ft 2 in (17.12 m)
Width10 ft 3+12 in (3.14 m)
Height15 ft 12 in (4.58 m)
Loco weight259,500 lb (117,700 kg)
Fuel capacity1,100 US gal (4,200 l; 920 imp gal)
Prime moverEMD 567C
RPM range835 max
Engine typeV16 Two-stroke diesel
AspirationRoots blower
Displacement9,072 cu in (148.66 L)
GeneratorEMD D-12-B
Traction motors(4) EMD D-37-B
Cylinder size8+12 in × 10 in (216 mm × 254 mm)
Performance figures
Maximum speed65 mph (105 km/h)
Power output1,750 hp (1.30 MW)
Tractive effort64,750 lbf (288.0 kN)
LocaleNorth America, South America

The EMD GP9 is a four-axle diesel-electric locomotive built by General Motors' Electro-Motive Division between 1954 and 1959. The GP9 succeeded the GP7 as the second model of EMD's General Purpose (GP) line,[1] incorporating a new sixteen-cylinder engine which generated 1,750 horsepower (1.30 MW).[2] This locomotive type was offered both with and without control cabs; locomotives built without control cabs were called GP9B locomotives.

EMD constructed 3,626 GP9s, including 165 GP9Bs.[3][4] An additional 646 GP9s were built by General Motors Diesel, EMD's Canadian subsidiary, for a total of 4,257 GP9s produced when Canadian production ended in 1963.[3] The GP9 was succeeded by the similar but slightly more powerful GP18.[5]

Design and Production[edit]

EMD designed the GP9 as an improved version of the GP7, with an increase in power from 1,500 hp to 1,750 hp, and a change in prime mover to the latest version of the 567 engine, the 567C.[5] Externally, the GP9 strongly resembled its predecessor. Most were built with high short hoods, but the Southern Pacific ordered a number with low short hoods for improved crew visibility.[5]

EMD built GP9s at its LaGrange, Illinois facility until 1959, when American production was ended in favor of the GP18.[5] GMD production in Canada continued until August 1963, when the final GP9 was produced.[3]


There were 40 GP9M units built that are included in the 3,441 units built for United States railroads. A GP9M was built with parts from another older EMD locomotive, either an F unit or a damaged GP7. The use of parts from these older locomotives caused the GP9Ms to have a lower power rating than a GP9. This would be either 1,350 horsepower (1.01 MW) if the donor locomotive was an FT/F2 or 1,500 horsepower (1.12 MW) from F3/F7/GP7 locomotives.

Many rebuilt GP9s remain in service today with shortline railroads and industrial operators. Some remain in rebuilt form on some major Class I railroads, as switcher locomotives although most Class 1 railroads stopped using these locomotives by the 1980s. Canadian National still had 29[6] GP9RM locomotives in operation, as of 2022. Canadian Pacific had many GP9u locomotives in operation; however, they were all retired in 2015.

Several GP9s were rebuilt with a 1,500 horsepower (1.12 MW) CAT 3512 and re-classified as GP15C.

The Illinois Central Railroad rebuilt some of its GP9s with their front (short) hood reduced in height for improved crew visibility. The IC designated these rebuilt locomotives GP10.

EMD has rebuilt and continues to rebuild GP9s into what it calls the GP20C-ECO, which is repowered with an EMD 8-710-G3A engine in place of the original 567 prime mover.[7]

A Canadian Pacific Railway EMD GP20C-ECO, the product of a GP9 rebuild.


At least 23 GP9 locomotives have been preserved at various railroad museums, as "park engines", and as excursion engines according to The Diesel Shop:

See also[edit]


  1. ^ Schafer, Mike. (1996-11-08). Classic American railroads. Osceola, WI. p. 103. ISBN 0760302391. OCLC 35033722.
  2. ^ Foster, Gerald L. (1996). "EMD GP9". A field guide to trains of North America. Boston: Houghton Mifflin. p. 28. ISBN 0395701120. OCLC 33242919.
  3. ^ a b c Marre, Louis A. (1995). Diesel locomotives : the first 50 years : a guide to diesels built before 1972. Waukesha, WI: Kalmbach Pub. Co. pp. 46–50. ISBN 0-89024-258-5. OCLC 34531120.
  4. ^ Wilson, Jeff (2017). Guide to North American diesel locomotives. Waukesha, Wisconsin. p. 58. ISBN 978-1-62700-455-8. OCLC 992348779.
  5. ^ a b c d Schafer, Mike (1998). Vintage diesel locomotives. Osceola, WI: Motorbooks International. p. 37. ISBN 0-7603-0507-2. OCLC 38738930.
  6. ^ Canadian Trackside Guide 2022. Ottawa: The Bytown Railway Society. 2022. p. 1-39.
  7. ^ "Repowered Locomotives". Progress Rail. Retrieved 2021-08-10.{{cite web}}: CS1 maint: url-status (link)
  8. ^ "B&O No.6607". B&O Railroad Museum. Retrieved 2021-08-10.{{cite web}}: CS1 maint: url-status (link)
  9. ^ "GGRM: Collection". www.ggrm.org. Retrieved 2021-08-10.
  10. ^ "Diesel Locomotives". Lake Superior Railroad Museum. Retrieved 2022-09-27.

External links[edit]