Cummins ISX12 G 400 6 Cylinder 11.9 L Compressed Natural Gas (CNG) 400 hp Engine, 2015 US EPA Label, Air Conditioner, Cruise Control, Power Windows, Engine Brake, Allison 4500 6-Speed Automatic Transmission, 12350 lb Front Axle, 22700 lb Rears, 35050 lb GVWR, Air Ride Cab, Aluminum Front Wheels, 295/75R22.5 Front Tires, 295/75R22.5 Rear Tires, Air Ride Suspension, 196 in Wheelbase, Air Sliding 5th Wheel