East Penn Rail Road (ESPN) GP18 Locomotive  No. 1804 at the end of their short line in Pennsburg, Montgomery County, Pennsylvania.

Photo by the Montgomery County Planning Commission.

(Montgomery County Planning Commission (Pennsylvania), CC BY-SA 2.0 <https://creativecommons.org/licenses/by-sa/2.0>, via Wikimedia Commons)



The EMD GP18 is a 4-axle diesel-electric locomotive built by General Motors, Electro-Motive Division between December 1959 and November 1963. Power was provided by an EMD 567D1 16-cylinder engine which generated 1,800 horsepower (1.34 MW). The GP18 replaced the GP9 in EMD's catalog. 350 examples of this locomotive model were built for American railroads, 40 units were built for Mexican railroads, 12 were built for export to a Brazilian railroad, 2 were exported to Peru, and 1 was exported to Saudi Arabia.


Ferrocarriles Nacionales de México (NdeM) EMD GP18 7504 at San Luis Potosi, San Luis Potosi, Mexico, March 7, 1975. Photographer: James C Herold.

This unit was built in June, 1961, as part of a the first order for 20 units, NdeM 7500-7519. NdeM owned a total of 37 bought over the next year.

(Craig Garver, Public domain, https://www.flickr.com/photos/digitalrailartist/51755074936/in/photolist-2mGCcne-2mGHXwW-2mRqhEd-2mGGt5g-2mGHDiS-2jHwLrH)


Design and Production

The GP18 in many ways resembled its predecessors, the GP7 and GP9. It was designed nearly identically to the two previous models, but differed in having a metal grid over its radiator shutters, while the GP7 and GP9 instead incorporated a design described as looking like "chicken wire". Additionally, the GP18 had 50 more horsepower than the GP9, for a total of 1,800 horsepower.

GP18s could be customized by their buyers: railroads ordered GP18s with either high or low short hoods, with or without dynamic brakes, and in the case of Grand Trunk Western, with the optional addition of steam generators.


Sonora Baja California EMD GP18 2306 at Mexicali, Baja California, March 22, 1976. Photographer: Thomas Chenowith.

(Craig Garver, Public domain, https://www.flickr.com/photos/digitalrailartist/51656674150/)


Original buyers

Railroad Quantity Road numbers Notes
Aberdeen and Rockfish Railroad 1 300
Baltimore and Ohio Railroad 1 6599 GP18M 1,750 horsepower (1,300 kW)
Boston and Maine Railroad 6 1750–1755 Mistakenly delivered as 1770–1775, but quickly renumbered to 1750-1755
Central of Georgia Railway 8 171–178 To Southern Railway 171–178
Chicago and North Western Railway 6 1774–1779
Grand Trunk Western Railroad 11 4700–4707, 4950–4952 4950-4952 equipped with steam generators
Illinois Central Railroad 29 9400–9428
Lehigh Valley Railroad 4 302–305 To Conrail 7496–7499
Louisville and Nashville Railroad 5 460–464 Renumbered 900–904, Then Seaboard System 1066–1070.
Missouri Pacific Railroad 146 400–499, 534–550, 4801-4829 400–499 built with AAR Type B trucks
New York, Susquehanna and Western Railway 3 1800, 1802, 1804 Sold in 2010 to East Penn Railroad
New York, Chicago and St. Louis Railroad (“Nickel Plate Road”) 10 700–709 To Norfolk and Western Railway 2700–2709
Norfolk and Western Railway 48 915–962
Norfolk Southern Railway 17 1–17 To Southern Railway 180–196
Northern Pacific Railway 9 376–384 To Burlington Northern Railroad 1990–1998
Phelps Dodge Corporation (New Cornelia Mine) 3 44–46
Chicago, Rock Island and Pacific Railroad 24 1238–1239, 1256, 1333–1353 1238–1239, 1256 are 1,500 horsepower (1,100 kW) GP18M.
Seaboard Air Line Railroad 10 400–409 To Seaboard Coast Line Railroad 1056–1065
Tennessee, Alabama and Georgia Railway 1 801 Renumbered 50 soon after delivery; to Southern Railway 179
Texas and Pacific Railway 5 1145–1149 To Missouri Pacific Railroad 500–504
Texas Mexican Railway 2 854–855
Toledo, Peoria and Western Railway 1 600 To Vermont Railway 801
National Railways of Mexico 37 7500–7536 7520-7529 equipped with steam generators
Ministry of Communication and Transportation (Mexico) 3 7123 - 5 to 7 To Sonora-Baja California 2304–2306
Araraquara Railway (Brazil) 12 1006–1017 1,600 mm (5 ft 3 in) gauge
Saudi Government Railways 1 1200 GP18M 1,500 horsepower (1,100 kW)
Southern Peru Copper Corp. 2 24-25
Total 405

An EMD GP18 owned and operated by FEPASA (formerly Araraquara Railway).

(Ricardo Frontera, CC BY-SA 3.0 <http://creativecommons.org/licenses/by-sa/3.0/>, via Wikimedia Commons)


EMD GP18 Overview

Type and origin
Power type: Diesel-electric
Builder: General Motors, Electro-Motive Division (EMD)
Model: GP18
Build date: December 1959 – November 1963
Total produced: U.S.- 350 units, Mexico- 40 units, export- 15 units. 405 units total.
​• AAR B-B
Gauge: Most units: 4 ft 8+1⁄2 in (1,435 mm) standard gauge; Brazilian units: 5 ft 3 in (1,600 mm)
Fuel capacity: 1,700 US gallons (6,400 L; 1,400 imp gal)
Prime mover: EMD 567D1
Engine type: V16 diesel engine
Aspiration: Roots blower
Cylinders: 16
Performance figures
Power output: 1,800 hp (1.34 MW)
Locale: United States, Mexico, Brazil, Peru and Saudi Arabia


Sonora Baja California EMD GP18 2305 at Mexicali, Baja California, September 3, 1972. Photographer: Thomas Chenowith.

(Craig Garver, Public domain, https://www.flickr.com/photos/digitalrailartist/51656383299/)