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EMD "GP38," "GP38-2," and "GP38AC": Data Sheet, Specs, Roster

Last revised: December 17, 2024

By: Adam Burns

The GP38 was a four-axle, mid-powered road-switcher produced by Electro-Motive from January, 1966 to December, 1971.  It was one of several new models the builder released in 1965 sporting the new 645 prime mover.

Designed for general freight service, over 700 units were produced by the time production had switched to the upgraded Dash 2 line in 1972.  There were only very minor differences between the GP38/GP38AC while the GP38-2's changes were almost entirely internal.

As Gerald Foster notes in his book, "A Field Guide To Trains," EMD masterfully read the market in the mid-1960s for a moderately powered road-switcher.  The entire GP38 series' production run  - which included the GP38, GP38AC, and GP38-2 and spanned two decades (1966-1986) - saw some 3,180 units produced. 

As a result of the GP38's success, hundreds remain in widespread use throughout the country, particularly on regionals and shortlines.  To date, there is only one currently-known GP38 officially preserved; Tennessee, Alabama & Georgia #80 at the Tennessee Valley Railroad Museum.

Photos

Lehigh Valley GP38-2's #319, #316, and #314 at work in the summer of 1973. American-Rails.com collection.

Overview

In his book, "EMD Locomotives," author Brian Solomon notes that in late 1965 the builder advertised nine new models equipped with its latest model 645 engine offered in a range of horsepower ratings, sizes, and wheel arrangements. 

Not every railroad at that time needed - or could handle - the big SD38s, SD40s, and SD45s.  As a result, there remained a strong demand for smaller, modestly powered models capable of handling a variety of assignments.

The GP38 fit this role perfectly.  It directly superseded the GP35, the final four-axle variant to carry the legendary 567 engine.  Aside from an upgraded prime mover and a carbody three feet longer than its predecessor, the GP38 was, externally, very similar.

At an undisclosed location not listed on the slide, a recently delivered Penn Central GP38 lays over between assignments in early October of 1969. American-Rails.com collection.

The first production GP38 was Detroit, Toledo & Ironton #200, completed in January, 1966.  Its 16-cylinder, model 645E engine, aspirated with Roots blowers, could produce 2,000 horsepower. 

The model initially featured a convential electrical system.  However, after 1971 EMD began offering an AC/DC system to handle the optional AR10 alternator in place of the standard D32 direct-current generator. 

The reasoning behind an alternator was space savings, as Louis Marre notes in his book, "Diesel Locomotives: The First 50 Years."

Missouri Pacific GP38-2 #2022 and SD40-2 #3277 at Taylor, Texas, circa 1982. Mike Bledsoe photo. American-Rails.com collection.

As horsepower ratings increased, the size of DC generators likewise increased.  With space inside an engine hood limited, the use of a more efficient alternator solved this problem.  The so-called GP38AC variant, however, saw only 261 examples produced to a handful of railroads.

In 1972, EMD released its "Dash 2" line, which included the GP38-2.  In his book, "Locomotives: The Modern Diesel & Electric Reference," author Greg McDonnell notes EMD listed 40 refinements to the Dash 2 line although nearly all of these were internal, aimed at improving locomotive efficiency and operation.

In doing so the GP38-2 was more reliable while also featuring increased tractive effort and reduced emissions.  Railroads loved the upgraded design; it was so successful EMD kept the GP38-2 in its catalog until 1985.  By the time production ended, some 2,213 units had been produced.

Norfolk & Western GP38AC #4107, wearing the experimental "Skunk" paint scheme bearing a large white strip around the carbody; December, 1982. Location not recorded. American-Rails.com collection.

Except for the later GP40 and GP40-2, the GP38 series was EMD’s most successful second-generation Geep and fit exactly what railroads were looking for in terms of horsepower and quality.

A brand new Gulf, Mobile & Ohio GP38AC, #727, at Bloomington, Illinois on April 3, 1971. Dick Wallin photo/Warren Calloway collection.

Spotting Features

The GP38 series is most easily distinguishable from other models by its twin exhaust stacks for its nonturbocharged 645E prime mover.  In addition, it featured only two rear radiator cooling fans, instead of the three found on the more powerful GP40 series.

However, identifying the GP38/GP38AC from the GP38-2 is a much more difficult undertaking.  Perhaps the most prominent feature is a water-level sight-glass window cut into the right-side hood door.

A former Rock Island GP38-2, formerly named the "Fred McKim," is ahead of this Missouri Pacific freight at Austin, Texas in May, 1980. Following the Rock's shutdown, Missouri Pacific picked up the railroad's fleet of GP38-2's. Mike Bledsoe photo. American-Rails.com collection.

One other notable characteristic is the use of EMD's latest truck design, the high-traction Blomberg-M.  It featured damping struts and rubber-buffered springs in place of leaf springs and was offered only on the GP38-2.

Finally, the Dash 2's sported bolted-on access plates for the battery box, which replaced the earlier hinged and latched design.  Burlington Northern, however, was one notable holdout for the older design, electng to have its Dash 2's equipped with the traditional setup.

Data Sheet

One of the Katy's few GP38's it owned, #303, is seen here at the shops in Parsons, Kansas in 1969. American-Rails.com collection.

Production Rosters

GP38

Total Built = 706

Reused Serials

Export

GP38AC

Total Built = 261

GP38-2

Total Built = 2,213

Export

General Motors Diesel Division (GMDD)

A set of six, new Burlington Northern GP38's were photographed here with time freight #97 (formerly Great Northern's "West Coaster") near Minot, North Dakota on March 3, 1970. Harr, Hedrich-Blessing photo. Author's collection.

B&O GP38 #3802

In 1982 Trains Magazine selected Baltimore & Ohio GP38 #3802 as its All American Diesel for the locomotive's performance, service, reliability and the fact that it was an extremely successful design found all across the country.   The unit ended its career on CSX as #9699.

The unit has since been retired from the roster and donated to the B&O Railroad Museum for preservation. Today it awaits restoration back into its original Chessie System colors (when it received its All American status) as well as the nameplates it originally received. 

Sources

• Foster, Gerald. A Field Guide To Trains. New York: Houghton Mifflin, 1996.

• Marre, Louis A. and Pinkepank, Jerry A. Contemporary Diesel Spotter's Guide, The: A Comprehensive Reference Manual To Locomotives Since 1972.  Milwaukee: Kalmbach Publishing Company, 1989.

• McDonnell, Greg. Locomotives: The Modern Diesel & Electric Reference, 2nd Edition. Buffalo: Boston Mills Press/Firefly Books, 2015.

• Solomon, Brian.  EMD Locomotives.  Minneapolis: MBI Publishing Company, 2006.

• Solomon, Brian.  GE and EMD Locomotives:  The Illustrated History.  Minneapolis:  Voyageur Press, 2014.