Because of the large number of tunnels (and snowsheds) found on the Southern Pacific, the railroad and EMD designed the SD45T-2 (and later the SD40T-2) in order to operate better in enclosed spaces. But even with a large fleet of these "Tunnel Motors," the SP still relied heavily on other locomotives - particularly their SD45s. Crossing the Santa Fe / Union Pacific mainline at the diamonds in Colton, California, SP SD45 8805 shows the tell-tale signs of time spent in tunnels in Oregon, Donner Pass and the Tehachapi Mountains - a heavy build-up of filth from the smokey tunnels that allow the railroad to cross massive mountains. Today, not only is the tower gone, but so is the crossing - replaced by an overpass as the old SP Sunset Route now crosses over the BNSF mainline. (SD45 would be destroyed in a wreck on the Union Pacific in Acoma, Nevada, in January 1995. It was scrapped on site.)