During 1992 it established the MK Rail Corporation to build locomotives and made an even bolder announcement, it would produce the most powerful, production road-switcher ever cataloged up until that time. The locomotive was listed as the MK5000C and would be manufactured at its Boise facility. The locomotive was 73 feet, 4 inches long and from the outside had the appearance of both established builders featuring notched-windows like EMD's but with a sloped nose commonly found on GE products. The carbody featured a very clean, unobstructed roofline with a beveled, EMD-like fuel tank. The MK5000C used its own, unique high-adhesion trucks and was powered by a 5,000 horsepower, Caterpillar model 3512, 12-cylinder prime mover.
It used a Kato main generator and MK's own, DC traction motors that offered 55,000 pounds of tractive effort. While the company was new to manufacturing its own line of locomotives with 22 years of rebuilding them it was not entirely a stranger to the process. During August of 1994 the first three MK5000Cs went into service, testing on the Southern Pacific. A year later three more were completed and began trials on the Union Pacific. By this time, parent Morrison-Knudsen was already experiencing serious financial problems as a result of its CEO, who was fired during February of 1995. To save the company, M-K was sold to the Washington Construction Group, Inc. which had little interest in the railroad industry and soon sold off its MK Rail subsidiary forming an independent entity known as MotivePower Industries Corporation.
Today, this operation is known as MotivePower, Inc. It is unfortunate that MK Rail never got a chance to thoroughly test and troubleshoot its new road-switcher. The six locomotives were sent back to MotivePower following the Morrison-Knudsen bankruptcy and debacle. Three more units were also in their early stages of production when the hammer fell. In 2001 the six completed units were sold to the Utah Railway with the three others scrapped by MotivePower. Utah experienced trouble with the locomotives and had them significantly overhauled with a new alternator (EMD), Electro-Motive's highly reliable 16-cylinder model 645F3B prime mover (in place of the CAT 3512), and reclassified them as the MK50-3. Overall, except for their exteriors the locomotives carry few original Morrison-Knudsen components. Today, you can still see them in regular service. For more information about the MK5000C please click here.
For a good book identifying various diesel models check out Gerald Foster's A Field Guide To Trains, which provides spotting guide information on how to ID different designs from the earliest FT through those released into the 1990s. Mr. Foster highlights both of Morrison-Knudsen's cataloged locomotives, the aforementioned MK5000C as well as the MK1200G, that was one of the first low-emission models ever put into servicing using a CAT prime mover and powered by natural gas. It was intended to operate in switcher/yard service with four manufactured and a pair each leased by Union Pacific and Santa Fe. Another excellent "spotters" guide is Locomotives: The Modern Diesel and Electric Reference by author Greg McDonnell that highlights more than 120 different models.