EMD SD40

The EMD SD40 is a model of 6-axle diesel-electric locomotive built by General Motors Electro-Motive Division between January 1966 and August 1972. 1,268 locomotives were built between 1966 and 1972. In 1972, an improved version with new electronics was developed and marketed as a new locomotive, the SD40-2.

Design

Like its predecessor in EMD's catalog, the SD35, the SD40 is a high-horsepower, six-axle freight locomotive. The SD40 is a member of EMD's long-running Special Duty class of locomotives, which all are built with 6 axles.

In 1966, EMD updated its locomotive catalog with entirely new models, all powered by the new 645 diesel engine. These included six-axle models SD38, SD40, SDP40 and SD45. All shared standardized components, including the frame, cab, generator, trucks, traction motors, and air brakes. The primary difference was the power output: SD38 = 2,000 hp (1,490 kW) from a non-turbocharged V16, SD40 = 3,000 hp (2,240 kW) from a turbocharged V16, and SD45 = 3,600 hp (2,680 kW) from a turbocharged V20.

Original owners

856 examples of this locomotive model were built for American railroads, 330 were built for Canadian railroads, 72 were built for Mexican railroads, 6 were built for the Guinea-Boke Project, and 4 SD40Ms riding on 5 ft 3 in (1,600 mm) gauge trucks were exported to Brazil. They were manufactured at McCook, Illinois.

Built by GMD at London, Ontario

Export SD40's Built by EMD at McCook, Illinois or GMD at London, Ontario

Phases are as listed by Robert Sarberenyi. [citation needed]

Derivatives and Experimental

The very first test bed SD40, EMD 434, constructed on an SD35 frame in July 1964 was in active service until retired by Canadian National Railway in March 2009 and donated to the Monticello Railway Museum in July 2009, albeit having been upgraded to an "SD40-2R", as Illinois Central 6071.

18 customized SD40s were built for the Illinois Central Railroad as model SD40A, using the longer SDP45 frame, which allowed for a larger 5,000 gallon fuel tank.

Versions of the SD40 modified for the Australian loading gauge were sold to WAGR and Victorian Railways as their L and C classes respectively.

The SD40 was succeeded by an upgraded Dash 2 version called the SD40-2.

SD40 rebuilds

After having been succeeded by the more modern SD40-2, a large number of SD40s have been upgraded with more modern equipment. The main difference between rebuilt SD40s and genuine SD40-2s is that the latter use a longer frame and have longer front and rear porches, while the rebuilt SD40s have a shorter frame.

A common product of rebuilding SD40s, and sometimes SD40-2s, is an SD40-3. The major addition denotes that the rebuilt unit or units as an SD40-3 is the addition of a micro-processor, and sometimes other modern components. The usual reasons for installing a micro-processor are improved traction control, and better fuel economy (via better injection control). Also, electronic control over braking systems (independent and automatic). This may include some SD39, SD45 and SD45-2 rebuilt to SD40-2 standards.

The SD40R is a rebuilt of all the Southern Pacific's SD40 between 1980 and 1981.

The SD40M-2 was a rebuild done by Morrison Knudsen for two railroads, the Southern Pacific, using 97 SD45s, 30 SD40s and 6 SDP45s, and the Canadian Pacific, using another three SD40s and seven SD45s.

The SD40-2XR designates 15 SD40 and a SDP40 rebuilt to Dash-2 standards for Montana Rail Link.[better source needed]

The SD40E is an SD50 rebuilt by the Norfolk Southern Railway and derated to 3000 HP (equivalent to an SD40-2).

SD40-series production timeline

Preservation

SD40

• Canadian Pacific SD40 #5500 is preserved at the Revelstoke Railway Museum in Revelstoke, British Columbia. It was CP's first SD40, built in 1966 at GMD's London plant and was retired in 2001. The unit was donated to the museum in 2007. Plans are being made to restore the locomotive to its original grey/tuscan red paint scheme, known as the Canadian Pacific "Script"

• Chesapeake and Ohio #7534 is preserved at the C&O Historical Society in Clifton Forge, Virginia. While #7534 spends most of its time at the Historical Society's museum, it sees occasional revenue service on the Buckingham Branch Railroad.

• CSX #4621 is preserved at the Western Maryland Scenic Railroad. It was donated by CSX in 2025. The WMSR plans to restore #4621 to its original appearance as Western Maryland #7496.

• Louisville and Nashville #1230 is owned by the Tennessee Valley Railroad Museum. The museum plans to use #1230 on the museum's for-profit subsidiary, the Tyner Terminal Railroad, It will eventually be restored to one of its earlier L&N liveries.

• Norfolk Southern #1580 is preserved by the Roanoke Chapter NRHS. It was donated by Norfolk Southern in 2024. It is presently being restored to its N&W "Pevler Blue" paint scheme.

• Santa Fe #5007 is preserved at the Western America Railroad Museum in Barstow, California. It's currently numbered GN 6307, after being donated to the museum by BNSF.

• Santa Fe #5008 is preserved at the Walt Disney Hometown Museum in Marceline, Missouri.

• Southern #3170 is preserved at the Tennessee Valley Railroad Museum in Chattanooga, Tennessee. Originally restored by Norfolk Southern in 2015 and used in revenue service, it was donated to the TVRM in 2016.

• Western Maryland #7471 is owned by Precision Locomotive Leasing and was leased to various shortlines, including Western Maryland Scenic Railroad, Steam Railroading Institute in Owosso, Michigan, and Buckingham Branch Railroad.

Rebuilds

• Illinois Central SD40-2R #6071, the first SD40 built, is preserved at the Monticello Railway Museum in Monticello, Illinois. It was donated in 2009. #6071 is preserved in near-operable condition, only needing new traction motors to operate.

Crew Training Programs

• PRLX 3066 (ex-KCSM #1343) is owned by the Coastal Pines Technical College in Waycross, Georgia. It is used to train prospective student engineers and conductors.

• Union Pacific SD40R #7362 is owned by the North Platte Community College in North Platte, Nebraska. It is used on the NPCC's North Campus as a training locomotive.

See also

• List of EMD locomotives
• List of GMD Locomotives

• Pinkepank, Jerry A. (1973). The Second Diesel Spotter's Guide. Milwaukee, Wisconsin: Kalmbach Publishing. ISBN 978-0-89024-026-7.
• Sarberenyi, Robert. . Retrieved on December 19, 2009
• Eck, H. C., The Modern Locomotive Handbook, 1977
• Service Department (1966). SD40 - SDP40 Operator's Manual. La Grange, IL: Electro-Motive Division of General Motors Corporation