An EMD GP40-2 locomotive switches in the yard in Readville, Massachusetts.

(4300streetcar, CC BY-SA 4.0 <>, via Wikimedia Commons)


gM-EMD logo Blue and white.

EMD GP40-2

The EMD GP40-2 is a 4-axle diesel-electric locomotive built by General Motors Electro-Motive Division as part of its Dash 2 line between April 1972 and December 1986. The locomotive's power is provided by an EMD 645E3 16-cylinder engine which generates 3,000 horsepower (2.24 MW).



Standard GP40-2 production totaled 861 units, with 817 built for U.S. railroads, 44 for Mexican railroads. Furthermore, 279 GP40-2s were built by General Motors Diesel (GMD) between 1974 and 1976. In addition, three GP40P-2s, passenger versions of the GP40-2, were built in 1974. Total production of the GP40-2 and its variations totaled 1,143 units.



With the 62:15 gearing (65-70 mph maximum) EMD rated the GP40-2 at 55,400 lb continuous tractive effort. Some had PF21 module that reduced the output below 23 mph, lowering continuous speed down to 11 mph.


Original buyers GP40-2

Owner Quantity Numbers Notes
Atlanta and West Point Rail Road 1 733 to Seaboard System Railroad to CSX
Alaska Railroad 10 3000, 3007–3015 3000 renumbered to 3006
Baltimore and Ohio Railroad 218 4100–4162, 1977, GM50, 4185–4256, 4287–4311, 4322–4351, 4422–4447 Chessie System paint to CSX
Boston and Maine Railroad 18 300–317
Chesapeake and Ohio Railway 95 4165–4184, 4267–4281, 4372–4421 Chessie System paint to CSX
Ferrocarril Chihuahua al Pacífico 29 1008–1036
Conrail 129 3275–3403 To CSX and Norfolk Southern Railway,
Denver and Rio Grande Western Railroad 37 3094–3130 All to Union Pacific Railroad.
U.S. Department of Transportation 1 003
Detroit, Toledo and Ironton Railroad 20 406–425 to Grand Trunk Western Railroad 6406–6425.
Florida East Coast Railway 24 411–434 433–434 were last built
Georgia Railroad 2 755–756 to Seaboard System Railroad to CSX
Kansas City Southern Railway 4 796–799
Louisville and Nashville Railroad 17 6600–6616 Family Lines Paint, to Seaboard System Railroad to CSX
Reading Company 5 3671–3675 to Conrail
Richmond, Fredericksburg and Potomac Railroad 7 141–147 to CSX
St. Louis – San Francisco Railway ("Frisco") 25 750–774 to Burlington Northern 3040–3064
St. Louis Southwestern Railway ("Cotton Belt") 56 7248–7273, 7628–7657
Seaboard Coast Line Railroad 25 1636–1656. 6617–6621 6617–6621 Family Lines paint; all to Seaboard System Railroad now CSX
Ferrocarril Sonora-Baja California 15 2104–2112, 2309–2314 2104-2112 have High short hoods w/steam generator for passenger service only GP40-2 built with high short hoods
Southern Pacific Transportation Company 68 7240–7247, 7608–7627, 7658–7677, 7940–7959
Texas, Oklahoma and Eastern Railroad 3 D15–D16, D20
Western Maryland Railway 35 4257–4261,4312–4321, 4352–4371 Chessie System paint to CSX
Western Pacific Railroad 15 3545–3559
Western Railway of Alabama 1 708 to Seaboard System Railroad to CSX
Total 861

MEC 507, a GP40-2LW locomotive. This locomotive was originally built for CN but later sold.

(4300streetcar, CC BY-SA 4.0 <>, via Wikimedia Commons)



Railroad Quantity Road numbers Notes
Canadian National Railway 268 CN 9400–9667, 9668–9677 CN 9400–9632 are GP40-2L, 9633–9677 are GP40-2W. CN 9668–9677 are former GO Transit units purchased in 1991.
GO Transit 11 GO 700–710 Ten to CN 9668–9677 in 1991. One (703) to Miami Tri-Rail, later sold to Aberdeen, Carolina & Western #703.
Total 279

SP GP40P-2 No. 3197 arriving in San Jose with the Peninsula Commute, March 1985.

(Drew Jacksich from San Jose, CA, The Republic of California, CC BY 2.0 <>, via Wikimedia Commons)



Railroad Quantity Road numbers Notes
Southern Pacific Transportation Company 3 3197-3199 renumbered to 7600,7601 & 7602. 7601 and 7602 went to UP as 1373 & 1375. 7600 went to IHB as 4010
Total 3


Union Pacific has rebuilt 129 of their GP40's and GP40-2's into GP40N's at their Jenk's shop. These units received a microprocessor control system to increase adhesion, control options, and extend the life of the locomotive.


St Louis Southwestern EMD GP40-2 7249 at Tucson, Arizona, November, 1984. Photographer: Craig Garver.

(Craig Garver, Public domain,

Southern Pacific

Southern Pacific bought 34 of these, some of the very last GP40-2's ever built, SP 7240-7247 and SSW 7248-7273. These Cotton Belt units arrived in October, and I shot this the next month. New power usually wandered on the eastern part of the system for a few months, to avoid taxes on new power in California, since it was a California corporation. As a 25 year old railfan, this was pretty tough to wait out, and new units were the subject of great anticipation by me.
It was always a supreme treat to watch something clean and shiny round the curve at Polvo and turn into the east end of PFE yard in Tucson. Sister unit 7250 is right behind, and both are on very likely their first trip to the coast.
These were the last units equipped new with oscillating headlights. In an attempt to reduce maintenance costs, SP equipped these units with Oscitrol lights. If you look carefully at the top headlight, you'll see each lens is aimed slightly differently, one a few degrees to the right, the other a few degrees to the left. It cut down on the expense of keeping a physically moving light in operation, and a safety appliance at that, but was not quite as effective as conventional gyralights. The top and bottom lights alternated coming on and off.
Soon enough would come the GP40 rebuilds from MK, the first equipped with ditch lights. My world would never quite be the same.
This power didn't last long. Once the UP took over, the leases expired on this order, and the asking price was too high to buy them, so they were returned after just fifteen years.
These units were unusual in other ways, too. The top walkways were covered in a black abrasive material for skid resistance, and only this power had the GP50-like air blower ducts to the traction motors.
This was the only power with the unusual headlight cluster on the rear of the unit, as you can see on the trailing locomotive.
They were certainly a treat to see them. - text by Craig Garver.



• Sonora Baja California 2107 is now preserved in a Museum in Mexicali, MX


RRRR GP-40s in Cañon City, Colorado heading west through the Royal Gorge.

(Jessica Hall, CC BY-SA 4.0 <>, via Wikimedia Commons)



Type and origin
Power type: Diesel-electric
Builder: General Motors Electro-Motive Division / General Motors Diesel (GMD)
Model: GP40-2
Build date: 1972–1986
Total produced: 1,143
​• AAR B-B
• UIC Bo'Bo'
Gauge: 4 ft 8+1⁄2 in (1,435 mm) standard gauge
Wheel diameter: 40 in (1.016 m)
Wheelbase: 43 ft (13.11 m)
Length: 59 ft 2 in (18.03 m)
Width: 10 ft 4 in (3.15 m)
Height: 15 ft 5 in (4.70 m)
Locomotive weight: 250,000 lb (113,398 kg)
Prime mover: EMD 16-645E3
Engine type: V16 diesel
Aspiration: Turbocharged
Cylinders: 16
Performance figures
Maximum speed: 65 mph (105 km/h)
Power output: 3,000 hp (2.24 MW)
Tractive effort: 61,000 lbf (27,669 kgf)