Cummins ISX15 6 Cylinder 15 L Ultra Low Sulfur Diesel 400 hp Engine, 2013 US EPA Label, Requires Diesel Exhaust Fluid, 18313 Engine hrs, Engine Brake, Eaton Fuller FM-15E310B 10-Speed Automated Transmission, 12000 lb Front Axle, 22700 lb Rears, Dana S23-190 Drive Axles, 2.53:1 Axle Ratio, 34700 lb GVWR, Air Ride Cab, 275/80R22.5 Front Tires, 295/75R22.5 Rear Tires, Airglide 4-Bag Air Ride Suspension, 158 in Wheelbase, Air Sliding 5th Wheel, Dual Fuel Tanks