TRI-DRIVE cab and chassis with 18 speed transmission, Cummins ISX engine with 450 HP, 20K front axle, 64K triple locking rears, Air Trac suspension, 425/65R22.5 front tires and 11R24.5 rear tires, 278" wheelbase, 334" bridge, and 24' frame behind the cab. 165,232 miles.