The Penn Central merger was just six months old when this Pennsy SD-45 showed up in Montreal on the daily freight from Massena, NY. For years, the power was two, four-axle units, typically RS-3's, FA's, Geeps and F units. Until the end of 1968 all sorts of big PRR units showed up in Montreal - SD-45, C628, U30C. By year end when PC had figured out that the big six-axle units were much more useful on Horseshoe Curve than in the flat lands of the St, Lawrence River Valley the four-axles returned, this time usually GP-40's or U25B's..
The EMD SD (special duty) series are a strong and reliable kind of locomotive which still serve America's rails today. They have proved themselves reliable by clocking in several million miles of freight service over several decades.
