The General Motors Locomotive Group (GMLG) Electro-Motive Division (EMD) SD70MAC is one of the most common locomotives plying the rails today. Originally introduced in late 1993 with an order for the Burlington Northern, the production now totals over 900 units, exceeding the combined production of the SD80MAC and SD90MAC locomotives by over 300 units.At this time, the SD70MAC, in all of its versions, has been operated by six different railroads in a total of eight different paint schemes. The railroads that operate this locomotive span from East to West and from Mexico to Alaska!