EMD GP7

General Motors Electro-Motive Division
Industry	Locomotive manufacturing
Founded	October 1949; 77 years ago
Headquarters	La Grange, Illinois, United States
Products	Diesel-electric locomotives

The EMD GP7 is a diesel-electric locomotive featuring four axles arranged in a B-B configuration according to the AAR wheel classification. Manufactured by General Motors Electro-Motive Division and General Motors Diesel from October 1949 through May 1954, it marked a significant development in locomotive design.

As EMD's inaugural road locomotive with a hood unit style rather than a traditional car-body, the GP7 introduced benefits such as reduced manufacturing expenses, simplified upkeep, and enhanced visibility during switching tasks. It was equipped with a 16-cylinder EMD 567B engine delivering , and was offered both with and without operator cabs; notably, five cabless variants known as GP7B were produced in 1953.

Out of the total 2,734 units constructed, 2,620 were deployed across American railroads—including five units for the Atchison, Topeka and Santa Fe Railway—while Canadian operators received 112 locomotives, and two were assigned to Mexican railroads.

The GP7 initiated EMD’s widely successful General Purpose series, introduced alongside the six-axle SD7 model. Eventually, the GP7 was succeeded within this lineup by the EMD GP9.

History

Prior to EMD’s entry into the road-switcher market, manufacturers such as ALCO, Fairbanks-Morse, and Baldwin had already developed similar models. EMD’s initial attempt with the BL2 proved unsuccessful, with only 58 units sold over a span of 14 months. The GP7 replaced the BL2’s truss-framed car body with a non-load-bearing body mounted on a welded steel frame—a structural approach that remains standard today. Although early GP7 frames exhibited bending under heavy operational stress, this issue was resolved in subsequent production runs.

The GP7 quickly gained popularity, with demand surpassing supply even after EMD established an additional manufacturing facility in Cleveland, Ohio. Later locomotives in the GP series earned the nickname "Geeps." Many GP7 locomotives continue to operate on shortline railroads and within industrial settings; some rebuilt versions remain active as switchers on major Class I railroad systems. The "GP" designation stands for "general purpose," while the number "7" corresponds to its contemporary counterpart, the EMD F7 cab unit.

Identification

The car-body design of the GP7 shares similarities with later models such as the GP9 and GP18, evolving over time. Typically, GP7 units feature three ventilation grills beneath the cab area (in contrast to a single grill on the GP9) and two pairs of grills at the rear of the long hood (where only one pair remains on the GP9). Some late-production GP7s have car bodies indistinguishable from early GP9s. Initial versions included solid skirts above the fuel tank; later models incorporated access openings that many railroads subsequently removed to facilitate inspections.

Control stands could be configured for operation with either the long or short hood leading; dual control stands were an option, but one end was designated as front for maintenance purposes. The GP7 could be ordered with or without dynamic brakes, and an optional steam generator installed in the short hood. For units equipped with steam generators, the fuel tank was divided to accommodate both diesel fuel and boiler water. In models lacking dynamic brakes, two air reservoirs located beneath the frame were sometimes replaced by four roof-mounted air tanks—often called "torpedo tubes"—which increased combined fuel and water capacity to . Certain railroads preferred roof-mounted air tanks paired with larger fuel tanks on their freight Geeps.

Locomotives built by Electro-Motive Division, USA

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Owner	Quantity	Numbers	Remarks
Electro-Motive Division (demonstrator)	1	525	GP7m with 1350 hp; initially Atchison, Topeka and Santa Fe 99, later renumbered to 2899. Equipped with a 567BC engine.
Electro-Motive Division (demonstrator)	3	100 (formerly 852), 200, 300	Delivered to Chicago & North Western as units 1518–1520. Unit 1518 is preserved at the Illinois Railway Museum.
Aberdeen and Rockfish Railroad	1	205
Atchison, Topeka and Santa Fe	244	2650–2893	Units 2855-2858 constructed with 567C engines.
Atchison, Topeka and Santa Fe	5	2788A–2792A	GP7B models; specifically, units 2788A-2789A and 2791A-2792A were built using 567C engines.
Atlanta and St. Andrews Bay	2	501–502
Atlanta and West Point Rail Road	5	571–575
Atlantic and East Carolina Railway	1	501	Later renumbered to 406.
Atlantic Coast Line Railroad	154	100–253
Baltimore and Ohio Railroad	33	720–731, 740–746, 910–922, 6405	"Long-hood-forward" configuration; units 728-729 and 740-746 were manufactured with 567BC engines.
Bangor and Aroostook Railroad	16	560–575
Belt Railway of Chicago	8	470–477
Boston and Maine Railroad	23	1555–1577
Totals	2,617 5	GP7 GP7B

Locomotives constructed by General Motors Diesel, Canada

The GP7 units were assembled at General Motors Diesel's London, Ontario facility for Canadian railroads as well as certain United States lines operating within southern Ontario, including C&O and Wabash.

Owner	Quantity	Numbers	Remarks
Algoma Central and Hudson Bay	21	150–170
Canadian National Railways	25	4824, 7555–7578	"Long-hood-forward" operation; unit 4824 was rebuilt in October 1958 using components from a wrecked F3A. Units 7555-7578 were renumbered to 4800-4823 in mid-1957.
Canadian Pacific Railway	17	8409–8425	Units 8410-8411 were originally equipped with steam generators.
Chesapeake and Ohio Railway	19	5720–5738	C&O units numbered 5720-5729 were later sold to NYC as numbers 5818-5827 for service in Canada.
Quebec North Shore and Labrador Railway	22	100–101, 104–123
Toronto, Hamilton and Buffalo Railway	7	71–77	All except the wrecked unit 71 were transferred to CP and rebuilt as CP units numbered 1682-1687.
Wabash Railroad	1	453	This unit was subsequently transferred to Norfolk & Western as number 3453.
Total	112

Rebuilds, modifications and conversions

According to A J Kristopan's EMD Serial Number listings, five GP7 units reused serial numbers during rebuilds: B&O 6405 (now preserved), CRI&P 1308 (second iteration), L&N 501 (second iteration), L&N 502 (second iteration), and SLSF 615 (second iteration). These locomotives were reconstructed on entirely new frames. A notable example includes CN 4824, which in October 1958 was rebuilt utilizing components from an F3A model.

Between March 1953 and May 1954, more than one hundred GP7s along with four GP7Bs were produced, all equipped with either 567BC or 567C engines.

Numerous railroads opted to upgrade their GP7 fleets by installing low short hoods; some undertook comprehensive alterations. The Missouri Pacific Railroad enhanced their units by fitting 567BC engines and substituting the original EMD two-stack exhaust system with a four-stack "liberated" exhaust, resulting in increased horsepower.

The Illinois Central Railroad extensively modernized most of their GP7 locomotives by installing 567BC engines, four-stack exhausts, paper air filters, and improved braking systems to ensure compatibility across operations. Except for the initial rebuilt unit, all featured lowered short hoods to enhance crew visibility. IC reclassified these rebuilt units as GP8 models. They procured numerous secondhand locomotives through Precision National Corporation (PNC) and offered GP8/GP10 rebuild programs at their Paducah Shops, where classifications were assigned based on power output rather than original model designation.

In 1960, the Alaska Railroad took possession of twelve GP7L units from the US Army; eleven underwent rebuilding in 1965 that included lowering the short hoods to improve clearance. One unit was rebuilt by Morrison-Knudsen in 1976, while nine others received refurbishments at Paducah Shops between 1976 and 1977.

During the early 1980s, the Canadian Pacific Railway modernized their GP7 locomotives into GP7u yard units. These upgrades involved chopping down the short hoods, updating number boards and cab windows, and replacing the original 567B prime movers with enhanced 645 power assemblies built to "BC" block specifications—some incorporating retired F-unit 567C blocks.

Preservation

A significant number of GP7 locomotives have been preserved and are currently held by tourist railroads and railway museums such as: