Paccar PX-6 6 Cylinder Ultra Low Sulfur Diesel 240 hp Engine, 15410 Engine hrs, Engine Brake, Allison 2500 Automatic Transmission, 12000 lb Front Axle, 21000 lb Rears, Dana S21-170 Drive Axles, 5.25:1 Axle Ratio, 33000.0 lb GVWR, 295/75R22.5, Air Trac Air Ride Suspension, 264 in Wheelbase, 192 in Cab to Axle, 310 in Cab to End of Frame