orologio en CB01 OFFICIAL. Donner Pass – the name evokes daunting obstacles with good reason. Steep grades and seven months a year of winter weather put a railroad's resources to the test. Yet the need to transport goods over the Sierras produces a nonstop parade of trains over this famous line, and that was especially true in 1988 when Video Rails captured incredible Southern Pacific action over Donner Pass. Starting at the classification yards in Roseville, California, you'll follow Southern Pacific's trains up and over "The Hill." SP's 6-axle SD40s, SD40T-2s, SD45s, and SD45T-2 tackle 138 miles of up to 2.4 percent grades. Up to 11 units are needed for the climb. The standard arrangement for these 10,000-ton trains is 4 by 6, with four engines leading and 6 mid-train helpers, but you'll also see long trains with six units leading, six mid-train helpers, and an end-of-train helper.