The EMD DDM45 is a narrow gauge diesel-electric 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 EMD. It has eight axles in two trucks, giving it a D-D wheel arrangement

Wheel arrangement

In rail transport, a wheel arrangement is a system of classifying the way in which wheels are distributed beneath a locomotive.. Several notations exist to describe the wheel assemblies of a locomotive by type, position, and connections, with the adopted notations varying by country...

. The name means a D-D locomotive, M for meter gauge, 45 series. They were built for service in Brazil, South America

South America

South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...

. The Estrada de Ferro Vitória a Minas (EFVM) bought several in the early 1970s in order to expand their locomotive roster. The EFVM needed the most powerful single-engined locomotive available, and the SD45

EMD SD45

The EMD SD45 is a six-axle diesel locomotive built by General Motors Electro-Motive Division between December, 1965, and December, 1971. Power was provided by an EMD 645E3 twenty-cylinder engine which generated 3,600 HP. This locomotive shared the same common frame with the EMD SD38, EMD SD39, EMD...

 represented the highest-rated model that EMD had to offer at the time.

However, a big locomotive such as an SD45 with its three-axle trucks wasn't readily adaptable to the EFVM's narrow gauge trackage. The smaller traction motor

Traction motor

Traction motor refers to an electric motor providing the primary rotational torque of a machine, usually for conversion into linear motion ....

s of the meter gauge locomotive were unable to handle the full current capacity from the 3600 hp prime mover. EMD proposed using a meter gauge version of the Flexicoil-D four-axle trucks

Bogie

A bogie is a wheeled wagon or trolley. In mechanics terms, a bogie is a chassis or framework carrying wheels, attached to a vehicle. It can be fixed in place, as on a cargo truck, mounted on a swivel, as on a railway carriage/car or locomotive, or sprung as in the suspension of a caterpillar...

, similar to those found under the domestic DD35

EMD DD35

The EMD DD35 was a diesel-electric locomotive of D-D wheel arrangement built by General Motors Electro-Motive Division for the Union Pacific Railroad and Southern Pacific Railroad. In the early 1960s Union Pacific started asking for a 15,000 hp 3-unit locomotive set to replace the turbines...

, DD35A

EMD DD35A

The EMD DD35A was a 5,000 hp diesel locomotive of D-D wheel arrangement built by General Motors Electro-Motive Division exclusively for the Union Pacific Railroad. They were a cab-equipped variant of the previous, cabless booster EMD DD35...

 and DDA40X

EMD DDA40X

The EMD DDA40X was a D-D diesel-electric locomotive built by the General Motors EMD division of La Grange, Illinois for the Union Pacific Railroad...

 locomotive models. The two additional traction motors of this design allowed full power to be used.

Roster of DDM45s:

Order number	Build date	Serial numbers	Country	Railroad	Numbers	Quantity
711197-711208	February 1970 - March 1970	34671-34682	Brazil	E. F. Vitória a Minas	801-812	12
711441-711448	March 1970 - April 1970	36303-36310	Brazil	E. F. Vitória a Minas	813-820	8
711871-711880	March 1971	37278-37287	Brazil	E. F. Vitória a Minas	821-830	10
712613-712621	March 1973 - April 1973	712613-712621	Brazil	E. F. Vitória a Minas	831-839	9
713096-713119	January 1974 - April 1974	713096-713119	Brazil	E. F. Vitória a Minas	840-863	24
713726-713735	October 1975 - December 1975	713726-713735	Brazil	E. F. Vitória a Minas	864-873	10
748027-1 to -10	January 1976 - March 1976	748027-1 to 748027-10	Brazil	E. F. Vitória a Minas	874-883	10