The EMD SD40 is a model of 6-axle

diesel-electric locomotive A diesel locomotive is a type of railway locomotive in which the power source is a diesel engine. Several types of diesel locomotives have been developed, differing mainly in the means by which mechanical power is conveyed to the driving whee ...

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 The EMD SD40-2 is a C-C diesel–electric locomotive built by EMD from 1972 to 1989. The SD40-2 was introduced in January 1972 as part of EMD's '' Dash 2'' series, competing against the GE U30C. Although higher-horsepower locomotives were av ...

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 A truck or lorry is a motor vehicle designed to transport freight, carry specialized payloads, or perform other utilitarian work. Trucks vary greatly in size, power, and configuration, but the vast majority feature body-on-frame construction ...

traction motors A traction motor is an electric motor used for propulsion of a vehicle, such as locomotives, electric or hydrogen vehicles, or electric multiple unit trains. Traction motors are used in electrically powered railway vehicles (electric multiple u ...

, and air brakes. The primary difference was the power output: SD38 = from a non-turbocharged V16, SD40 = from a turbocharged V16, and SD45 = from a turbocharged V20.

Original owners

856 examples of this locomotive model were built for American railroads, 330 were built for

Canadian Canadians () are people identified with the country of Canada. This connection may be residential, legal, historical or cultural. For most Canadians, many (or all) of these connections exist and are collectively the source of their being ''C ...

railroads, 72 were built for Mexican railroads, 6 were built for the

Guinea-Boke Project Guinea has 1,155km of railways. This comprises 366km at Rail gauge, gauge and 789km at gauge. The latter includes 662km in common carrier service from Kankan to Conakry most of which is abandoned. The current status Conakry to Kankan (sta ...

, and 4 SD40Ms riding on gauge trucks were exported to Brazil. They were manufactured at

McCook, Illinois McCook is a village in Cook County, Illinois, United States, and is an industrial suburb of Chicago. As of the 2020 census, the village population was 249, which is the lowest population of all municipalities in the county. History McCook was n ...

. Built by GMD at

London, Ontario London is a city in southwestern Ontario, Canada, along the Quebec City–Windsor Corridor. The city had a population of 422,324 according to the 2021 Canadian census. London is at the confluence of the Thames River (Ontario), Thames River and N ...

Mexican SD40's Built by EMD at

or GMD at

Phases are as listed by Robert Sarberenyi.

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 The Canadian National Railway Company () is a Canadian Class I freight railway headquartered in Montreal, Quebec, which serves Canada and the Midwestern and Southern United States. CN is Canada's largest railway, in terms of both revenue a ...

in March 2009 and donated to the

Monticello Railway Museum The Monticello Railway Museum (initialism, initialized MRYM, reporting mark MRMZ) is a non-profit railway museum, railroad museum located in Monticello, Illinois, about 18 miles west of Champaign, Illinois. It is home to over 100 pieces of railro ...

in July 2009, albeit having been upgraded to an "SD40-2R", as

Illinois Central The Illinois Central Railroad , sometimes called the Main Line of Mid-America, is a railroad in the Central United States. Its primary routes connected Chicago, Illinois, with New Orleans, Louisiana, and Mobile, Alabama, and thus, the Great Lak ...

6071. 18 customized SD40s were built for the

Illinois Central Railroad The Illinois Central Railroad , sometimes called the Main Line of Mid-America, is a railroad in the Central United States. Its primary routes connected Chicago, Illinois, with New Orleans, New Orleans, Louisiana, and Mobile, Alabama, and thus, ...

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

Australia Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...

n loading gauge were sold to WAGR and

Victorian Railways The Victorian Railways (VR), trading from 1974 as VicRail, was the state-owned operator of most rail transport in the Australian state of Victoria from 1859 to 1983. The first railways in Victoria were private companies, but when these companie ...

as their L and C classes respectively. The SD40 was succeeded by an upgraded Dash 2 version called the

SD40 rebuilds

After having been succeeded by the more modern SD40-2, a large number of SD40 have been upgraded with more modern equipment. The main difference between rebuilt SD40 and genuine SD40-2 is that the latter use a longer frame and has longer front and rear porches, while the rebuilt SD40 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 The Southern Pacific (or Espee from the railroad initials) was an American Class I railroad network that existed from 1865 to 1996 and operated largely in the Western United States. The system was operated by various companies under the names ...

'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 Montana Rail Link (now operated by BNSF as the MRL Subdivision) was a privately held Class II railroad in the United States. It operated on trackage originally built by the Northern Pacific Railway and leased from its successor BNSF Railway. ...

. The SD40E is an SD50 rebuilt by the

Norfolk Southern Railway The Norfolk Southern Railway is a Class I freight railroad operating in the Eastern United States. Headquartered in Atlanta, the company was formed in 1982 with the merger of the Norfolk and Western Railway and Southern Railway. The comp ...

and derated to 3000 HP (equivalent to an

SD40-series production timeline

DateFormat = mm/dd/yyyy ImageSize = width:900 height:auto barincrement:30 Period = from:01/01/1966 till:01/01/1990 TimeAxis = orientation:horizontal PlotArea = right:30 left:0 bottom:50 top:5 Colors = id:barcolor value:rgb(0.99,0.7,0.7) id:line value:black id:bg value:white PlotData= width:20 textcolor:black shift:(5,-5) anchor:from fontsize:s bar:1 color:powderblue from:01/01/1966 till:08/31/1972 text:SD40 (Jan 1966 - Aug 1972, 1,268 units produced) bar:2 color:powderblue from:06/01/1966 till:05/31/1970 text: SDP40 (June 1966 - May 1970, 20 units produced) bar:3 color:powderblue from:01/01/1969 till:01/01/1970 text: SD40A (1969 - 1970, 18 units produced) bar:4 color:powderblue from:01/01/1972 till:10/31/1989 text:

(Jan 1972 - Oct 1989, 3,957 units produced) bar:5 color:powderblue from:06/01/1973 till:08/31/1974 text: SDP40F (June 1973 - Aug 1974, 150 units produced) bar:6 color:powderblue from:04/01/1974 till:07/31/1980 text: SD40T-2 (Apr 1974 - July 1980, 312 units produced) bar:7 color:powderblue from:05/01/1975 till:12/31/1980 text: SD40-2W (May 1975 - Dec 1980, 123 units produced) bar:8 color:powderblue from:04/01/1978 till:05/30/1978 text: SD40-2S (Apr 1978 - May 1978, 5 units produced; Nov 1980, 4 units produced) bar:8 color:powderblue from:11/01/1980 till:11/30/1980 bar:9 color:powderblue from:06/01/1979 till:07/01/1979 text: SD40X (1979, 4 units produced) ScaleMajor = gridcolor:line unit:year increment:1 start:01/01/1966 TextData = fontsize:L textcolor:black pos:(370,30) # tabs:(0-center) text:"SD40-Series Production Timeline"

Preservation

• Ex-

Canadian National The Canadian National Railway Company () is a Canadian Class I freight railway headquartered in Montreal, Quebec, which serves Canada and the Midwestern and Southern United States. CN is Canada's largest railway, in terms of both revenue an ...

SD40 #5232 (built November 1971) has been purchased by The Vintage Locomotive Society on January 10, 2015, from Cando and the

Central Manitoba Railway The Central Manitoba Railway is a Canadian shortline railway operating in the province of Manitoba Manitoba is a Provinces and territories of Canada, province of Canada at the Centre of Canada, longitudinal centre of the country. It is ...

. It is being used for revenue service by Prairie Rail Solutions, a wholly owned subsidiary of the Society. The unit has been repainted completely black, with Prairie Rail Solutions lettering and logos. It is VLSX 5232. •

Canadian Pacific The Canadian Pacific Railway () , also known simply as CPR or Canadian Pacific and formerly as CP Rail (1968–1996), is a Canadian Class I railway incorporated in 1881. The railway is owned by Canadian Pacific Kansas City, Canadian Pacific Ka ...

SD40 #5500 is preserved at the Revelstoke Railway Museum in Revelstoke, BC. It was CP's first SD40, built in 1966 at GMD's

London London is the Capital city, capital and List of urban areas in the United Kingdom, largest city of both England and the United Kingdom, with a population of in . London metropolitan area, Its wider metropolitan area is the largest in Wester ...

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 look as it was when ordered, including a repaint into its original grey/tuscan red paint scheme, known as the Canadian Pacific "Script". • Chesapeake and Ohio #7534 has been donated by CSX Transportation to the C&O Historical Society in Clifton Forge, Virginia. This engine is well known in the railroad enthusiast community as it ran on CSX right up to the late-2000s still wearing some of it original C&O paint and lettering, and was the very last SD40 on CSX's roster. The engine was meant to be used on the Buckingham Branch Railroad, which also operates out of Clifton Forge, however the unit spends quite a bit of time at the Historical Society's museum. •

SD40-2R #6071, the first SD40 built, is preserved at the Monticello Railway Museum in Monticello, Illinois. It was originally EMD demonstrator #434. It was sold to the Gulf Mobile & Ohio and it became GM&O #950. The GM&O was later merged into the Illinois Central Railroad and became Illinois Central Gulf #6071, then later rebuilt into an SD40-2R for the IC. It was donated March 11, 2009. The engine is fully functional, however it needs new traction motors if it were to operate again. • Kansas City Southern de México SD40 1343 (as PRLX 3066) is owned by the Coastal Pines Technical College in Waycross, Georgia and is used to train kids that are looking to work for CSX • Louisville and Nashville #1230 is owned by the

Tennessee Valley Railroad Museum The Tennessee Valley Railroad Museum is a railroad museum and heritage railroad in Chattanooga, Tennessee. The Tennessee Valley Railroad Museum was founded as a chapter of the National Railway Historical Society in 1960 by Paul H. Merriman a ...

but will be put to work on the museum's for-profit subsidiary, the Tyner Terminal Railroad, switching the

Volkswagen Volkswagen (VW; )English: , . is a German automotive industry, automobile manufacturer based in Wolfsburg, Lower Saxony, Germany. Established in 1937 by German Labour Front, The German Labour Front, it was revitalized into the global brand it ...

plant. It will eventually be restored to one of its earlier L&N liveries. • Ex-Santa Fe #5007 (built 1966 as ATSF 1707) is preserved at the Western America Railroad Museum in

Barstow, California Barstow is a city in San Bernardino County, California, in the Mojave Desert of Southern California. Located in the Inland Empire region of California, the population was 25,415 at the 2020 United States census, 2020 census. Barstow is an impor ...

. It's currently numbered GN 6307, after being donated to the museum by BNSF. • Santa Fe #5008 (built 1966 as ATSF 1708) is preserved at the

Walt Disney Hometown Museum The Walt Disney Hometown Museum is located in the restored Santa Fe Railway Depot in Marceline, Missouri. Opened in 2001, the museum houses a collection of memorabilia from the Disney family's farm where they lived from 1905 to 1909 along with ...

Marceline, Missouri Marceline is a city in Chariton County, Missouri, Chariton and Linn County, Missouri, Linn counties in the U.S. state of Missouri. The population was 2,123 at the 2020 United States census, 2020 census. History In 1887, the Chicago, Santa Fe, an ...

. In mid December, 2014, it was revealed that Norfolk Southern had set aside two SD40 units, that were retired in 2007, for preservation: * NS SD40 #1580, built for the

Norfolk and Western The Norfolk and Western Railway , commonly called the N&W, was a US class I railroad, formed by more than 200 railroad mergers between 1838 and 1982. It was headquartered in Roanoke, Virginia, for most of its existence. Its motto was "Precisio ...

, was donated to the Roanoke Chapter NRHS on 3/25/24. * NS SD40 #3170, built as Southern #3170, the first SD40 bought by the Southern. It was restored to operating condition at the

Juniata Shops Altoona Works (also known as Altoona Terminal) is a large railroad industrial complex in Altoona, Pennsylvania. It was built between 1850 and 1925 by the Pennsylvania Railroad (PRR), to supply the railroad with locomotives, railroad cars and re ...

Altoona, Pennsylvania Altoona ( ) is a city in Blair County, Pennsylvania, United States. The population was 43,963 at the time of the 2020 United States census, 2020 census. It is the principal city of the Altoona Metropolitan statistical area, metropolitan area, w ...

, and then sent to the NS Paint shops at the Debutts Yard in

Chattanooga, Tennessee Chattanooga ( ) is a city in Hamilton County, Tennessee, United States, and its county seat. It is located along the Tennessee River and borders Georgia (U.S. state), Georgia to the south. With a population of 181,099 in 2020, it is Tennessee ...

, where it made its public debut February 27, 2015. It operated on the NS Coastal Division. On May 18, 2016, it was donated to the

Norfolk Southern The Norfolk Southern Railway is a Class I freight railroad operating in the Eastern United States. Headquartered in Atlanta, the company was formed in 1982 with the merger of the Norfolk and Western Railway and Southern Railway. The comp ...

. •

Union Pacific The Union Pacific Railroad is a Class I freight-hauling railroad that operates 8,300 locomotives over routes in 23 U.S. states west of Chicago and New Orleans. Union Pacific is the second largest railroad in the United States after BNSF, ...

#7362 (built 1966 as SP #8475) is used on North Platte Community College's North Campus as a training locomotive. •

Western Maryland upright=1.2, An enlargeable map of Maryland's 23 counties and one independent city Western Maryland, also known as the Maryland panhandle or Mountain Maryland, is the portion of the U.S. state of Maryland that typically consists of Washing ...

#7471 is owned by Precision Locomotive Leasing and currently leased to the

Steam Railroading Institute The Steam Railroading Institute is a non-profit organization that preserves, restores, and operates historical railroad equipment and items. Located in Owosso, Michigan, it was founded in 1969 as the Michigan State University Railroad Club and la ...

Owosso, Michigan Owosso () is the largest city in Shiawassee County in the U.S. state of Michigan. The population was 14,714 at the 2020 census. It is located west of Flint, and northeast of Lansing. The city is mostly surrounded by Owosso Township on its we ...

. It was formerly owned by George's Creek Railroad. * Western Maryland #7496, still in CSX livery was donated to Western Maryland Scenic Railroad in April 2025.

References

* * Sarberenyi, Robert.
EMD SD40, SD40A, and SDP40 Original Owners
'. 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 {{Authority control

SD40 SD40 may refer to: * Canon PowerShot SD40, a digital camera * EMD SD40, a diesel-electric locomotive * South Dakota Highway 40 * SD-40 alcohol, ethanol denatured alcohol, denatured by adding denatonium benzoate * School District 40 New Westminster, ...

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