Cat C15 6 Cylinder 15.2 L Diesel Engine, 2006 US EPA Label, Eaton Fuller RTLO-16913A 13-Speed Manual Transmission, 12000 lb Front Axle, 38000 lb Rears, 3.25:1 Axle Ratio, 50000.0 lb GVWR, Aluminum Wheels, 11R22.5 Front Tires, 295/75R22.5 Rear Tires, Air Ride Suspension, 230 in Wheelbase, Air Sliding 5th Wheel, Dual Fuel Tanks