GM V8 8.1 L Gasoline 340 hp Engine, 2005 US EPA Label, CARB Compliant, Allison M75 5-Speed Automatic Transmission, 6250 lb Front Axle, 13500 lb Rears, 5.13:1 Axle Ratio, 16000 lb GVWR, 225/70R19.5 Front Tires, 225/70R19.5 Rear Tires, GM Spring Suspension, 189 in Wheelbase, General 13 ft x 96 in Wide x 102 in High Body, Liftgate, liftgare