Santa Fe EMD GP40X No. 3801 rests in the afternoon sunshine of August 30, 1986, at the railroad’s locomotive facility at Corwith Yard in Chicago, Illinois. Flared radiators are a feature of the 23 GP40X testbeds built as frontrunners of EMD’s 50 Series, with these 3,500 hp prototypes carrying the new 16-645F3 engine.
