The front and rear sets of drive axles are free to roll out of phase with respect to each other.

Its most distinguishing feature was that the cab and firebox were at the front of the locomotive instead of the traditional rear.

[3][page needed] The cab-forward design was useful in the long tunnels and snow sheds of Donner Pass and other mountainous regions where it kept smoke, heat, and soot away from the operating crew, allowing them to breathe clean air in such enclosed spaces.

4294 to the City of Sacramento, California, where it was put on outdoor display October 19, 1958 at the SP station next to the C. P. Huntington, the railroad's first locomotive.

Construction for Interstate 5 necessitated a move for the locomotive and it was stored in the SP shops until May 1981.

According to CSRM personnel, the biggest impediments toward such a project are the estimated costs and the current policies of both Union Pacific Railroad and BNSF Railway in regards to operations.