From the dawn of the diesel era to the early 1990s EMD was king on Southern Pacific's Sierra Crossing between Roseville, CA and Sparks, NV. By the mid-90s new Southern Pacific General Electric AC4400s began to make ripples followed swiftly by a tidal wave of armour yellow GEs that came following the UP-SP merger in 1996. Harkening back to a time when the sound of whining EMD dynamic brakes was so unmistakable on Donner Pass, Union Pacific's eastbound Roseville, CA to Roper, UT manifest is entrusted to a set of 5 EMD SD70 series machines as it slips through the horseshoe curve between the old SP stations of Polaris and Union Mills.
