Cummins X15 6 Cylinder Ultra Low Sulfur Diesel Engine, Air Conditioner, Cruise Control, Power Windows, Engine Brake, Automatic Transmission, 13200 lb Front Axle, 40000 lb Rears, 53200 lb GVWR, Air Ride Cab, Aluminum Wheels, 11R22.5 Front Tires, 11R22.5 Rear Tires, Air Ride Suspension, 189 in Wheelbase, Air Sliding 5th Wheel, Dual Fuel Tanks