Motive Power Industries
MotivePower Industries (MPI) is a division of the Wabtec Corporation, and is a supplier of parts for many railroad, bus and truck manufacturers, as well as offering manufacturing and rebuilding of locomotives.
Although the MPI name only dates back to 1996, it's history can be traced back to the 1960s. Morrison-Knudson was a large construction firm and in the mid-1960s began to rebuild locomotives for various railroads. Over time they developed the capability to build their own locomotives, as well as improving existing designs. In fact, they are most well known for their upgrades of EMD's F40PH.
In the early 1990s it was decided that the now-spun off MK Rail would develop its own locomotive lineup. Its centerpiece would be the MK5000C, a 6-axle, 5000hp DC traction monster that was unveiled in 1994. While there was some interest in the model, as well as their switchers, the sale of parent Morrison-Knudson to Washington Group Corporation as well as the divestiture of MK Rail ended all hopes of a third entrant into the loco builders race. In fact, there is evidence that Southern Pacific was so impressed by their 3 MK5000C demos that they approached MK Rail for a 60 unit order, but were turned down.
MK Rail was spun off to become MotivePower Industries, and for a couple of years succeeded in returning to its core operations: rebuilding locomotives. In 1999 it merged with the Westinghouse Air Brake Company (WABCo) to become Wabtec, with the MPI name remaining as the railway division.
MPXpress series passenger locomotive
MP20D switcher locomotive