An EMD SD40A is a six-axle diesel locomotive

Locomotive

A locomotive is a railway vehicle that provides the motive power for a train. The word originates from the Latin loco – "from a place", ablative of locus, "place" + Medieval Latin motivus, "causing motion", and is a shortened form of the term locomotive engine, first used in the early 19th...

 built by General Motors Electro-Motive Division between 1969 and 1970. 18 examples of this locomotive were built exclusively for the Illinois Central Railroad

Illinois Central Railroad

The Illinois Central Railroad , sometimes called the Main Line of Mid-America, is a railroad in the central United States, with its primary routes connecting Chicago, Illinois with New Orleans, Louisiana and Birmingham, Alabama. A line also connected Chicago with Sioux City, Iowa...

. The SD40A was basically an SD40

EMD SD40

The EMD SD40 is a 6-axle diesel locomotive built by General Motors Electro-Motive Division between January 1966 and August 1972.-Design:Like its predecessor in EMD's catalog, the SD35, the SD40 is a high-horsepower, six-motor freight locomotive....

 built on an SDP45

EMD SDP45

The EMD SDP45 was a six-axle, C-C, diesel locomotive built by General Motors' Electro-Motive Division of La Grange, Illinois. It was fundamentally a passenger-hauling version of the SD45 on a stretched locomotive frame and with an extended, squared-off long hood at the rear, aft of the radiators,...

 frame. The longer SDP45 frame allowed for a larger, 5000 gallon fuel tank. This locomotive is powered by a sixteen-cylinder

Cylinder (engine)

A cylinder is the central working part of a reciprocating engine or pump, the space in which a piston travels. Multiple cylinders are commonly arranged side by side in a bank, or engine block, which is typically cast from aluminum or cast iron before receiving precision machine work...

 EMD 645E3 diesel engine, which could provide 3000 hp. Illinois Central Railroad used the SD40A as a long-range road-switcher, utilizing the larger fuel tank found on the SDP45. The Soo Line Railroad

Soo Line Railroad

The Soo Line Railroad is the primary United States railroad subsidiary of the Canadian Pacific Railway , controlled through the Soo Line Corporation, and one of seven U.S. Class I railroads. Although it is named for the Minneapolis, St. Paul and Sault Ste...

 eventually acquired five of these units and as of 2005 they are out of service. Six other units (IC 6011, and 6013-6018) remain in service under IC, which is now a subsidiary of Canadian National Railway

Canadian National Railway

The Canadian National Railway Company is a Canadian Class I railway headquartered in Montreal, Quebec. CN's slogan is "North America's Railroad"....