Ten-year-old Southern Pacific 7201 lays over at the railroad's Dolores Yard. Built by EMD in February 1978, this GP40X originally featured "elephant ears" over its flared radiators in order to draw cooler air into the engine while operating in tunnels. SP purchased four GP40Xs, and as with the Union Pacific’s six, they were delivered with experimental HT-B trucks, intended to improve adhesion to the rails. These trucks had a slightly longer wheelbase (9-feet 9?-inches) than the standard Blomberg M trucks (at just 9-feet), and they also used 42-inch wheels rather than the Blomberg M's 40-inch wheels. Due to their rarity (only 23 were built) and flared radiators, GP40Xs were favorites of railfans. (Carson, California – June 1988)
