General Motors Electro-Motive Division built just seven SD45X diesels in 1970 – four demonstrators and three for Southern Pacific Railroad. EMDX 4201-4203 were built with SP's typical array of ... (more)

A Rare EMD SD45X 5740 was one of only 7 of this model that were built. This unit was the EMD demo. It was In Williams with test cars to test the New GP40X unit that was on the other end of the ... (more)

SD45X 5740 leads an EMD test train at the Depot In Williams Arizona in the early morning

EMD SD45X demonstrator is the trailing unit of a westbound SP manifest departing Roseville Yard at Antelope. The SP purchased these demos, renumbering this one SP 9503. The 45Xs, like the DDA40Xs,... (more)

Maybe it was an SD55. In any case EMDs test string was reportedly working on the Saluda grade which was still open then. These units varied in many features over the years and were iinteresting ... (more)

EMD SD45X, a 4,200-horsepower testbed, leads a westbound merchandise train at Norden in January 1975.

One of seven SD45Xs (three wore SP colors), 9501 delivered 4,200 hp 17 years before GE was able to reach 4,000 hp with the C40-8. Kodak ISO 200 print, Leica M-3, Summicron 50mm f2.