The EMD GP15, technically listed by the builder as the GP15-1, was a late model
of the General Purpose series intended by Electro-Motive to be,
essentially, an updated version of their GP7, GP9, or GP20 for light
duty use (such as on branch lines or yard service). Those models
were also being rebuilt during the GP15's era, the late 1970s, and
EMD's intent with the design was also to provide railroads the option of just purchasing new. The GP15 sold relatively well for a four-axle model
during the time that railroads were beginning to heavily favor six-axle
units (the phenomenally successful SD40-2 was in production at the
time), although just a handful of Class Is ultimately purchased it. It
also came offered in two different variants; the GP15T and GP15Today,
several GP15s remain in service on Class I systems (such as Union
Pacific and CSX Transportation) as well as smaller lines.
The Chicago & North Western purchased a fleet of 25 GP15-1s in 1976; here, brand new units #4401 and #4404 switch the small yard in downtown Duluth, Minnesota during August of 1976.
The EMD GP15 (also known as the GP15-1) began production in the early
summer of 1976 as an updated version of the builder's early GP models like the GP7 and GP9. It featured General Motors' latest prime mover at the time, the 12-cylinder model 645E, which could produce a respectable 1,500 horsepower. Using a B-B truck setup (as did all GP series locomotives) and GM's model
D77 traction motor the GP15 could produce 48,000 pounds of continuous
tractive effort and 61,000 pounds continuous. Visually, the EMD GP15
looked like a shorter version of the more powerful GP38-2/GP39-2, which
were being manufactured during the time. The model was only a little less than 55-feet in length but featured EMD's low-nose, "Spartan Cab" (also known as the standard cab).
Constructed during the height of EMD's reign of manufacturing leader,
the company intended the GP15 to be an alternative for railroads looking
to rebuild older Geeps like their first generation GP7s and GP9s (and
other manufacturer's models still in service at that time such as early
designs built by the American Locomotive Company, Baldwin, and Fairbanks
Morse). It is very likely that EMD realized that their would not be a
high demand for such a specialized model like the GP15 understanding that many lines would probably find it cheaper to simply rebuild older units. And, to a greater degree
the company was correct as few Class Is ultimately purchased the GP15.
When production had ended on the variant GP15T (which was turbocharged)
in the spring of 1983 just five Class Is purchased 338 examples.
Overall buyers for all variants of the GP15 included the Chesapeake
& Ohio (28 GP15Ts), Apalachicola Northern (3 GP15Ts), Chicago &
North Western (25), Conrail (100), Missouri Pacific (160 GP15s and 30
GP15ACs), IAFFE of Venezuela (4 GP15ACs), and the Frisco (25).
CSX GP15T #1521 leads a mixed freight through Hammond, Indiana on May 30, 1991. This unit began its career as C&O #1521 in 1982.
As mentioned above there were two variants of the GP15; the GP15T and the GP15AC. The former model was offered by EMD with an 8-cylinder model 645 prime mover
that featured a turbocharger (thus the "T" designation). Equipped with
fewer cylinders but offering the same horsepower as the standard GP15 it
was far more fuel efficient, thus an operational savings to the
railroads that purchased it, the C&O/Chessie System and Apalachicola
Northern (of note, the former's GP15Ts were equipped with dynamic
brakes while the AN's were not). It was built between October, 1982 and
April, 1983 with a total of 34 constructed.
Missouri Pacific GP15-1 #1629 and a mate lead a freight through El Dorado, Arkansas on September 22, 1983.
The latter model, the GP15AC, was requested by the MoPac to feature the
model AR10, alternating current (AC) alternator instead of the standard
General Motors' model
D32 direct current (DC) generator. The railroad purchased 30 examples
of the locomotive while foreign line IAFFE of Venezuela picked up
another 4. Interestingly, while few railroads purchased the EMD GP15,
many remain in service today as the Class Is which inherited those
purchased by their predecessors continue to find the model a reliable
and useful light duty unit, notably in yard service. Places you can
GP15s in service include UP, CSX, California Northern, Dallas, Garland
& Northeastern, Wisconsin Northern, Gulf, Colorado, & San Saba,
Puget Sound & Pacific, Utah Central, and Larry's Truck &