The General Motors’
Electro-Motive Division (EMD) GP7 series was built for both freight and
passenger use (primarily the former), and would find immense success,
even eclipsing its predecessor models to become one of the most success diesel locomotive
designs ever built. The “covered wagons” (slang for the E and F
series) would signal the beginning of the end for steam and in just
twenty years following the first EA model
produced in the mid 1930s, steam would all but disappear from main line
railroading (the introduction of GP7 was, perhaps, the final nail in
the proverbial coffin for steam). A year before the GP7's introduction,
EMD had unveiled the BL2 model that was intended to be its grand
entrance into the road switcher market and compete with Baldwin,
Fairbanks Morse, and the American Locomotive Company (Alco) in
particular, which had been manufacturing the model for nearly a decade.
However, the BL2 still lacked essential design characteristics dooming
its success. EMD learned from this mistake and sales exploded with the
GP7, which quickly surpassed its competition. The locomotive was so
reliable and well built that many remain in service with shortlines
Electro-Motive's first GP7 demonstrator, #100, is seen here performing switching work likely in Chicago during the fall of 1949 shortly after she was built.
As mentioned above, EMD's entrance into the road switcher market began
with the BL2 design of 1948. The company was frustrated that it was not
only far behind the other builders in releasing a similar model but
also that Alco, at the time, controlled the road switcher market with
its "Road Switcher", RS, series. Up until that time the company was
offering railroads two different models, the RS1 and RS2 (along a few
variants) that had sold an astonishing 1,200 examples in just eight
years. While only moderately powered the RS1 and RS2 offered
unparalleled flexibility for train crews with its thin long hood and
This, in turn, allowed for walkways down the length of the locomotive,
and even to the front where a short hood was located. Additionally,
with a semi-streamlined carbody and that short, lead hood Alco's road
switchers were ideal for limited passenger service as well. While both
Baldwin and FM offered similar designs like the DRS-4-4-1500 and H15-44,
none were as successful as Alco's early lines. As such, EMD took
inspiration from this as well as the failures of its BL2. Spearheading
the redesign was once again, EMD's chief engineer
Richard "Dick" Dilworth who was instrumental in the development of the
phenomenally successful FT of 1939. Realizing that they already had a
reliable and practical locomotive on their hands and simply needed to
offer railroads a carbody that was functional Dilworth stripped down the
BL2 and started from scratch.
Chicago & North Western GP7 #1635 tiptoes its way through the weedy yard in Freeport, Illinois on the late afternoon of August 17, 1964. The C&NW was a big buyer of this model purchasing more than 100 examples.
He replaced the full length hood with a narrower design and off-set the
cab, allowing for a short lead hood. The locomotive was not quite as
beveled as the road switchers offered by Alco, Baldwin, and FM.
However, it carried its own stylish appearance with flush lines and
tapering at each end. The roof line was likewise clean where it was flush with the cab, unlike in Alco's and Baldwin's models
but similar to FM's. Dubbed the "General Purpose" series or Geep for
short to reflect the locomotive's duties as a road switcher the first
was named the GP7 and cataloged in October, 1949. The number "7" was
chosen as both the E7 and F7 cab units, as well as the switcher model SW7 were all in production at that time.
Belt Railway of Chicago GP7 #477 runs long-hood forward as it heads up a freight at Hegewisch, Illinois during the late winter of 1964.
The GP7 carried all of the features that made EMD so highly regarded
with its ease of maintenance and nice design features. The locomotive
had an added incentive in that along with being able to handle
practically any type of freight service
with its 1,500 horsepower rating, the GP7's overall carbody design was
also attractive enough to be used in many types of passenger service,
which is fascinating in the sense that the the model really offered no
type of streamlining. It was thanks to EMD's styling department headed
then by John Markestein, who along with Dilworth helped create the
now-classic look of the GP7. Through 1954 the model sold an astounding
2,700+ units and is widely credited with completing main line
dieselization, relegating most remaining steam locomotives to branch
line, yard and short line work (an exception would be the Norfolk &
Western, which held out on scrapping its steam fleet until the late
As mentioned above the GP7 carried a horsepower rating of 1,500, which again was not uncommon with amongst the models being offered by Alco, Baldwin, and FM. It used EMD's standard prime mover of the time, 16-cylinder model 567B and featured components built almost entirely by General Motors, which was standard for virtually all of its models. These included things like the main generator (model D12), traction motors (model D27B), and alternator (model
D14). However, just like with the other manufactures it outsourced air
brakes to Westinghouse with the compressor provided by Gardner-Denver.
With a tractive effort of 65,000 pounds starting and 40,000 pounds
continuous these ratings could not quite match Fairbanks Morse or
Baldwin but their models did not offer the reliability of EMD.
Burlington GP7 #234 has a way freight at Downers Grove, Illinois on the afternoon of July 30, 1965.
EMD manufactured four demonstrators; #100, #200, #300, and #525 to
tour the country in an elegant blue and silver livery. For railroads,
it was just what they were hoping for; practicality for use by train
crews with the EMD reliability that they expected. As such, sales
quickly took off. It should be noted that there was one request for
GP7Bs from the Santa Fe who purchased five in the early spring of 1953,
numbered 2788A-2792A. Also, the model was most commonly built with the
high hood but some railroads requested a lowered version in the later
standard cab design, which included front windshields (GP7s would also
be rebuilt with shortened hoods). Still commonly found today on
several regionals and shortlines the GP7 is the classic image of the
road switcher with its high, short hood and cab set off to one end
leaving for a long hood trailing.
Richmond, Fredericksburg & Potomac GP7s #102 and #103 switch local customers at Ashland, Virginia on September 16, 1969. The RF&P owned just four examples of this model.
Not surprisingly, with the railroad’s love for the locomotive it
was given a nickname that is now synonymous with the GP series; using
the model’s initials, “GP,” the locomotives became affectionately known
as Geeps (pronounced “Jeeps”). The GP7 was, however, only the beginning
of the series and later four-axle, as well as six-axle models would
follow. Because of the GP7s lightweight but strong pulling power it
was purchased by not only Class Is but also smaller lines.
Additionally, with EMD's Canadian division, General Motors Diesel of
Ontario established in 1949 the company also sold 112 examples to the
Algoma Central & Hudson Bay, Canadian National,
Canadian Pacific, Chesapeake & Ohio (for its southern Ontario
lines), Quebec North Shore & Labrador, Toronto, Hamilton &
Buffalo, and Wabash.