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ATSF 309 (Flickr 22322834666).jpg
Santa Fe Railway F7 #309 with the Grand Canyon Limited on August 19, 1967
Type and origin
Power typeDiesel-electric
BuilderGeneral Motors Electro-Motive Division (EMD)
General Motors Diesel (GMD, Canada)
Build dateFebruary 1949 – December 1953
Total produced
Gauge4 ft 8+12 in (1,435 mm)
TrucksBlomberg B
Wheel diameter40 in (1,016 mm)
Minimum curve23° (250.79 ft or 76.44 m radius)
Wheelbase39 ft (11.89 m)
LengthA unit: 50 ft 8 in (15.44 m)
B unit: 50 ft 0 in (15.24 m)
Width10 ft 7 in (3.23 m)
Height15 ft (4.57 m)
Loco weight247,300 lb (112,200 kg)
Prime moverEMD 16-567B
RPM range800
Engine typeTwo-stroke V16 diesel
AspirationRoots blower
Displacement9,072 cu in (148.66 L)
GeneratorEMD D-12
Traction motors(4) EMD D-27-B
Cylinder size8+12 in × 10 in (216 mm × 254 mm)
Performance figures
Maximum speed65–102 mph (105–164 km/h)
Power output1,500 hp (1,100 kW)
Tractive effortStarting: 56,500 lbf (251 kN) @25%
Continuous: 40,000 lbf (180 kN) @9.3 mph (15 km/h)
LocaleNorth America

The EMD F7 is a model of 1,500-horsepower (1,100 kW) diesel-electric locomotive produced between February 1949 and December 1953 by the Electro-Motive Division of General Motors (EMD) and General Motors Diesel (GMD).

Although originally promoted by EMD as a freight-hauling unit, the F7 was also used in passenger service hauling such trains as the Santa Fe Railway's Super Chief, & El Capitan and Ontario Northland's Northlander.


The F7 was the fourth model in GM-EMD's successful line of F-unit locomotives, and by far the best-selling cab unit of all time. In fact, more F7s were built than all other F-units combined. The F7 succeeded the F3 model in GM-EMD's F-unit series, and was replaced in turn by the F9. Final assembly was at GM-EMD's La Grange, Illinois, plant or GMD's London, Ontario, facility. There was no F4, -5 or -6 model; "7" was chosen to match the contemporary twin-engine E7, and was also applied to the new GP7 road-switcher.

The F7 differed from the F3 primarily in internal equipment—mostly electrical—and some external features. Its continuous tractive effort rating was 20 percent higher, e.g. 40,000 lbf (180 kN) for an F7 with 65 mph (105 km/h) gearing, compared to 32,500 lbf (145 kN) for an F3 with the same gearing.

A total of 2,393 cab-equipped lead A units and 1,463 cabless-booster or B units were built.[1]

Many F7s remained in service for decades, as railroads found them economical to operate and maintain. However, the locomotive was not very popular with yard crews who operated them in switching service because they were difficult to mount and dismount, and it was also nearly impossible for the engineer to see hand signals from a ground crew without leaning way outside the window. As most of these engines were bought and operated before two-way radio became standard on most American railroads, this was a major point of contention. In later years, with the advent of the "road switchers" such as the EMD GP7, F-units were primarily used in "through freight" and "unit train" service where there was little or no switching to be done.

Engine and powertrain[edit]

The F7's prime mover is a 16-cylinder 567B series diesel engine developing 1,500 hp (1.1 MW) at 800 rpm. The 567B is a mechanically aspirated two-stroke design in a 45-degree V engine configuration, with 567 cu in (9.29 L) displacement per cylinder, for a total of 9,072 cu in (148.66 L).  A direct current generator that is mechanically coupled to the flywheel end of the engine powers four traction motors, with two motors mounted on each Blomberg B truck. EMD has built all of its major components since 1939.[2][3][4][5] Starting in August 1953 EMD installed 567BC and 567C engines in a few F7s, see roster below.


There are no easily identifiable differences between late F3 production and early F7 production; the major differences were all internal electrical system changes. However, no F7 had the "chicken wire" grilles seen on most F3s, and no F3s had later F7 changes described below under Phases.

The F9 is distinguishable from the late F7 by having five, rather than four, carbody center louver groups covering the carbody filters. The additional one is placed ahead of the first porthole, where F7s have no openings. The F9's greater power output, of course, cannot be seen from the outside.

There were also two main classes of F7s: passenger and freight. Most passenger units had upper and lower headlights, but there were exceptions. Many freight units had the upper Mars or Pyle brand warning light as well. And some passenger units only had a single upper headlight, i.e. the Pennsylvania. Many units eventually had the upper lights or the door light removed/plated over and the Mars/Pyle light removed. These early warning lights had a motor and linkages that often required maintenance in the shops.

Original buyers[edit]

Locomotives built by Electro-Motive Division, USA[edit]

Railroad Quantity
A units
B units
Road numbers
A units
Road numbers
B units
Electro-Motive Division (demonstrators) 7 801–802,1950A,B,5040,459A,D 801–802 to Great Northern 272A,B,

1950A,B to Louisville & Nashville 857–858

5040 to Union Pacific 1483

459A,D to Union Pacific 1481–1482

Electro-Motive Division (test unit) 1 - 930A 930 to B&M 4268A
Electro-Motive Division (demonstrators) 6 459B,C,7002–7003,9052–9053 to Union Pacific 1496B,C (B units)

7002–7003 FP7-F7B-F7B demonstrators; to Soo Line (Wisconsin Central) 2500B–2501B

9052–9053 FP7-F7B-F7B demonstrators; to Soo Line 500B–501B

Atlantic Coast Line Railroad 77 12 317, 348–423 392B–403B FT 317 wrecked, November 1950; rebuilt as F7 317:2, May 1951. Wrecked again in a head-on collision with F7 417, October 1956; both rebuilt as F9 317:3 and 417:2, May 1957.


Atlantic Coast Line Railroad (C&WC) 6 900-905
Alaska Railroad 5 4 1500–1508 (even) 1501–1507 (odd) 1506–1508 were built with 567BC engines
Atchison, Topeka and Santa Fe Railway 215 247 37,C–47,C, 202,C–280,C, 300–316, 306–314 (second), 336–344 37A,B–47A,B, 48A, 202A,B–280A,B, 300A,B–316A,B, 306A,B–314A,B (second), 336A,B–340A,B, 341A–344A 37–47 passenger, 202-280 freight, 300-344 dual service (passenger and freight), 48A rebuilt by EMD from Santa Fe F3B 32A (1st), used by EMD as a demo for several years. 269LABC-280LABC were built with 567BC engines.
Bessemer and Lake Erie Railroad 28 26 701A–728A 701B–726B
Boston and Maine Railroad 3 4 4265A–4267A 4265B–4268B EMD Test Unit 930 to B&M 4268A, B&M 4266A and 4268A are now owned by 470 Railroad Club and leased to the Conway Scenic Railroad in North Conway, NH, both are in operation but 4268 was rebuilt from a donor unit NHN GP9r 1757. The 4265A is in Gorham, NH owned by the Gorham Historical society and is in poor condition with no current plans for restoration.
Baltimore and Ohio Railroad 157 100 180,A–192,A (even), 231–237 (odd), 239,A–297,A (odd), 361,A–365,A (odd), 367–374, 929,A–973,A (odd), 975, 977,A–993,A (odd) 180X,AX–192A,AX (even), 153X–171Z (odd), 231X–237X (odd), 249X–297X (odd), 361X, 363X,AX, 365X,AX, 367X,AX–374X,AX (odd & even), 929X–961X (odd), 977X–993X (odd)
Chicago, Burlington and Quincy Railroad 10 3 163A–166A, 167A,C–169A,C 167B–169B
Chicago Great Western Railway 4 20 153–156 104B, 105D–112D, 113B,D–116B,D, 116E,F,G
Chicago and North Western Railway 72 22 4067A,C–4102A,C 4067B–4084B, 4091B–4094B
Chicago, St. Paul, Minneapolis and Omaha Railway ("Omaha Road") 12 6500A,C–6505A,C 6501A was rebuilt to EMD F9A test unit 462
Chicago, Rock Island and Pacific Railroad 31 17 100–127, 675–677 100B–109B, 120B–123B, 675B–677B 675–677 passenger
Chesapeake and Ohio Railway 94 54 7000–7093 7515–7546, 8500–8506 8500s passenger (with FP7)
Clinchfield Railroad 15 11 806–820 853–863 In addition, F3As 800-805 and F3Bs 850-852 were rebuilt by EMD as F7s.
Colorado and Southern Railway 6 6 700A,D–702A,D 700B,C–702B,C
Delaware, Lackawanna and Western Railroad 9 6 611A,C, 631A,C, 632A–636A 611B, 632B–636B
Denver and Rio Grande Western Railroad 43 40 5481, 5551/4, 5571/4–5761/4 5552/3, 5572/3–5742/3, 5752, 5762
Erie Railroad 6 6 711A,D–713A,D 711B,C–713B,C 713 ABBA set was originally numbered 807A-D
Fort Worth and Denver City Railway 6 6 750A,D–752A,D 750B,C–752B,C
Gulf, Mobile and Ohio Railroad 4 10 811B, 812A,B, 813A B65–B74
Great Northern Railway 63 49 268A–270A, 271A,B, 273A,B–275A,B, 280A–281A, 307A,C–309A,C, 311A,C–317A,C, 350A, 360A, 364A,C–365A,C, 444A,D–456A,D (even), 460A,D, 462A,D–468A,D (even) 268B–270B, 280B–281B, 307B–309B, 311B–317B, 350B, 360B, 364B–365B, 444B,C–456B,C (even), 458C, 460B,C, 462B,C–468B,C (even), 500B–504B 350–365, 500s passenger
Kansas, Oklahoma and Gulf Railway 4 2 751–754 755B–756B
Kansas City Southern Railway 11 14 59D (twice), 70A,C–71A,C, 72A,D–73A,D, 74A 33B, 59B,C, 70B–71B, 72B,C–75B,C, 78C (second)
Kansas City Southern (Louisiana and Arkansas Railway) 7 8 32A–33A, 74D, 75A,D–76A,D 32B, 76B,C–78B,C, 79B
Louisville and Nashville Railroad 67 17 800–856, 844–849, 900–903 703–716, 900–902
Lehigh Valley Railroad 8 6 560–574 (even) 561–571 (odd)
Milwaukee Road 68 50 48A,C–50A,C, 68A,C–79A,C, 84A,D–85A,D, 86A, 87A,C–89A,C, 106A–108A, 109A,C–111A,C, 113A,C–121A,C 48B–50B, 68B–79B, 84B,C–85B,C, 87B–105B, 109B–111B, 113B–121B 90B–105B passenger (with FP7)
Missouri–Kansas–Texas Railroad 16 8 208A,C–211A,C, 226A,C–229A,C 208B–211B, 121B–124B
Missouri Pacific Railroad 26 10 577–594, 619–626 587B–594B, 629B–630B
Missouri Pacific Railroad (International-Great Northern Railroad) 14 2 595–606, 617–618 595B–596B
Missouri Pacific Railroad (St. Louis, Brownsville and Mexico Railway) 10 607–616
Minneapolis and St. Louis Railway 8 150A,C, 250A,C, 350A,C, 151A,C
Nashville, Chattanooga and St. Louis Railway 23 8 809–831 912–919
Northern Pacific Railway 45 34 6007A,D–6020A,D, 6500C -6502C, 6507A,C–6513A,C 6007B,C–6020B,C, 6050B, 6510B–6513B, 6550 6000s freight (as dual service locomotives), 6500s passenger
New York Central Railroad 238 56 1636–1873 2420–2474, 2446 (second)
Pennsylvania Railroad 123 76 9640A–9676A, 9690A–9699A, 9764A–9831A, 9872A–9879A 9547B–9555B (odd), 9640B–9647B, 9648B–9660B (even), 9667B–9676B, 9764B–9818B (even), 9832B–9858B (even), 9872B–9878B (even)
Reading Company 18 6 266–283 266B–271B
Richmond, Fredericksburg and Potomac Railroad 10 10 1101–1110 1151–1160
St. Louis–San Francisco Railway 22 22 5018–5039 5118–5139 F7A to 18 – 39 after renumbering

F7B to 118 – 139 after renumbering

Soo Line 6 2 212A,B–214A,B 502B, 503B 500s passenger (with FP7)
Soo Line (Wisconsin Central Railway 20 4 2201A,B–2203A,B, 2224A,B–2230A,B 2201C–2204C 2228AB-2230AB were built with 567C engines.
Southern Railway 63 44 4207–4269 4385–4428
Southern Railway (CNO&TP) 7 24 6114–6120 6160–6183
Southern Railway (AGS) 6 3 6714–6719 6756–6758
Southern Pacific Railroad 250 220 6140A,D–6169A,D, 6240–6423, 6440–6445 6140B,C–6169B,C, 8140–8285, 8290–8303
Southern Pacific Railroad (T&NO) 44 16 338–381 538–553
Southern Pacific Railroad (SSW) 28 17 SSW 920D (923), 921 2nd, 925–975 (odd) 926–958 (even) SSW 920D (923) was an FT rebuilt on an F7 underframe, SSW 921 2nd was an FT rebuilt on an F7 underframe
Spokane, Portland and Seattle Railway 4 803–806 to BN 9754,9756,9758,9760
Texas Mexican Railway 2 800A,B
Texas and Pacific Railway 83 35 1500–1582 1500B–1534B
Union Pacific Railroad 18 36 1464–1465, 1466 (twice), 1467–1480 1464B,C, 1466B,C (twice), 1468B,C–1494B,C (even), 910B,C 910B,C with FP7
Wabash Railroad 96 9 1100,A–1108,A, 1140,A–1154,A, 1165,A–1188,A 1100B–1108B F7A's to Norfolk and Western #3631-3726, F7B's to #7616-7624
Western Maryland Railway 26 14 53–66, 231-242 53B–65B (odd), 231B–243B (odd) WM 61B, 65B, 239B, 241B, and 243B were built with 567C engines.
Western Pacific Railroad 24 26 913A,D–924A,D 804B–805B, 913B,C–924B,C 800s passenger (with FP7)
Totals 2269 1422

Locomotives built by General Motors Diesel, Canada[edit]

Railroad Quantity
A units
B units
Road numbers
A units
Road numbers
B units
Canadian National Railways 58 18 9028–9142 (even) 9029–9063 (odd)
Canadian Pacific Railway 29 4424–4448, 4459–4462 Ordered with FP7
Wabash Railroad 22 1155,A–1164,A, 1189,A Ordered for service in Canada
Totals 80 47

Export locomotives built by Electro-Motive Division, USA for Mexico[edit]

Railroad Quantity
A units
B units
Road numbers
A units
Road numbers
B units
Ferrocarriles Nacionales de México 22 16 6310–6318, 6319A–6327A, 6335–6338 6319B–6334B
Mexican Ministry of Communications and Public Works ("SCOP") 2 23037–23038
Totals 24 16


MARC Train #83, a former B&O F7 rebuilt into an F9PH, at Brunswick, Maryland in 1994.

Several F7s were rebuilt by Morrison–Knudsen as F9PHs and used in passenger operations. Others were rebuilt as the "FP10" and used by the Massachusetts Bay Transportation Authority for their commuter rail service. In addition, the Santa Fe had 190 of their F7As rebuilt into CF7 hood units in the 1970s. Only one original F7 unit from the railway exists to this day.

In the early 2000s, a single unpowered EMD F cab unit #7100 (ex-Baltimore & Ohio Railroad F7 #4553) operated on MARC, occasionally substituting for a cab car. In addition to serving as an all-purpose control unit, it also had a head-end power generator that supplied electricity to the train.[6]

Surviving units[edit]

The Escanaba and Lake Superior Railroad's F7A seen on April 29, 2009, while stopped in Channing, Michigan.
Boston & Maine 4266 at the Conway Scenic Railroad in North Conway, N.H., seen on October 9, 2004.
Western Pacific Railroad F7A: 923A, later operated by Mt. Newman Mining as 5451, seen on April 28, 2012.

Several F7s survive today, mostly in museums and tourist railroads.

  • The Norfolk Southern Railway previously rostered four F7 units (two A units and two B units), all which were rebuilt in 2007. The two A units were rebuilt into F9PH units, and rebuilt again into F9A units. They were used on inspection trains and Office Car Specials until 2019, when NS sold the four units.[7][8] Two of them were sent to the Aberdeen, Carolina and Western Railway, while the other two were sent to the Reading Blue Mountain and Northern Railroad.[9][10]
  • The Escanaba and Lake Superior Railroad (as of October 2011) operates an FP7A (#600) in main line freight service. The unit is the former Milwaukee Road #96A, and was purchased in 2005 from the Wisconsin and Southern Railroad.[11]
  • The California State Railroad Museum in Sacramento, California, has three F7s.
    • Western Pacific F7A 913: This engine is currently listed as serviceable.
    • Atchison, Topeka & Santa Fe No. 347C GM-EMD 1949 F7A was given as a gift to the museum by Santa Fe in March 1986 and is repainted to original warbonnet colors. Currently inoperable.
    • Southern Pacific No. 6402 GM-EMD 1952 F7A was also given as a gift by the Pacific Coast Chapter of the Railroad and Historical Society in June 1978. Part of the locomotive has since been cutaway to display the inner workings of a diesel locomotive.[12]
  • The Don Rhodes Mining and Transport Museum at Port Hedland, Western Australia, has a former Western Pacific Railroad F7A: 923A. It was sold to Mt. Newman Mining and operated as locomotive #5451 before being transferred to the Shire of Port Hedland.[13][14] It is now a static display, with the prime mover removed.
  • The Galveston Railroad Museum owned F7As Texas Limited #100 (ex-Southern Pacific #6379) and #200 (ex-Southern Pacific #6309). This duo headed the "Texas Limited" passenger train which made runs to and from Houston until track speed restrictions and liability insurance costs ended operations.[when?] Both units were scrapped in 2011 after extensive damage resulting from being submerged in saltwater after Hurricane Ike. The museum now owns 2 more F7's, #315 and #316, which are both painted in ATSF warbonnet colors. Both units are ex-Southern Pacific, #'s 6443 (315) and 365 (316); they have parts salvaged from the Texas Limited units.[15]
  • Ex-Chicago and North Western Railway No. 401, formerly one of the C&NW’s executive train units in the 1980s, was donated by the Union Pacific Railroad to the Boone and Scenic Valley Railroad, which plans to restore the locomotive to operation. It arrived on the railroad on March 10, 2023.[16]

See also[edit]


  1. ^ Cook 2015, p. 30
  2. ^ Pinkpank, Jerry A (1973). The Second Diesel Spotter's Guide. Kalmbach Books. pp. 13, 26, 90–101. ISBN 0-89024-026-4.
  3. ^ Ross, David, ed. (2003). The Encyclopedia of Trains and Locomotives. pp. 261, 273. ISBN 978-0-7607-9679-5.
  4. ^ EMD 567C Engine Manual, EMD F7 Operators Manual
  5. ^ Kettering, E.W. (November 29, 1951). History and Development of the 567 Series General Motors Locomotive Engine. ASME 1951 Annual Meeting. Atlantic City, New Jersey: Electro-Motive Division, General Motors Corporation.
  6. ^ "The MARC 7100 Returns! (November 1999 CSX Railfan Magazine)". TrainWeb. Retrieved September 1, 2012.
  7. ^ "AltoonaWorks.info -- NS F Unit Rebuilds".
  8. ^ "NS to dispose of executive F units, other roster oddities | Trains Magazine".
  9. ^ https://www.rbmnrr.com/happenings/2019/11/24/reading-amp-northern-buys-two-of-nss-fab-four-f-units-updatedZ[dead link]
  10. ^ "Last two NS F-units sold to North Carolina short line | Trains Magazine".
  11. ^ Glischinski, Steve (2007). Regional Railroads of the Midwest. St. Paul, Minnesota: MBI Publishing Company. ISBN 978-0-7603-2351-9.
  12. ^ "Internal Combustion Locomotives" Archived February 13, 2015, at the Wayback Machine. California State Railroad Museum Foundation. Retrieved 28 February 2015.
  13. ^ Radecki, Alan. "The Western Pacific Surviving Locomotive List". Railfan.net. Retrieved August 25, 2013.
  14. ^ (untitled) Archived October 13, 2007, at the Wayback Machine
  15. ^ Duncan, Stephan. "History Of The Warbonnets". Galveston Railroad Museum. Retrieved January 25, 2016.
  16. ^ "F unit donated by Union Pacific arrives at Iowa heritage railroad". Trains. Retrieved March 14, 2023.


External links[edit]