813 w/winch= Manual trans, NHC250 Cummins, stock 11.00x20 tires, air over hydraulic brakes, cab slightly smaller than a 939 series
925= Auto trans, NHC250 Cummins, air brakes, stock 11.00x20 tires, slightly larger cab
925A1= Auto trans, NHC250 Cummins, air brakes, stock single 14.00x20 tires...