The workhorse of Amtrak’s California Zephyr has been the GE P42DC engine, also known by the name ‘Genesis’. The engine’s 4,250 horsepower engine has a maximum speed of 110 mph and they were built from 1993 to 2001. While some have been lost to accidents and some have been rebuilt, the majority of the 321 produced are still pulling passenger cars across Amtrak's US longer haul, higher speed routes and Canada's Quebec City-Windsor rail corridor.