Detroit DD15 14.8 L Ultra Low Sulfur Diesel 505 hp Engine, 2015 US EPA Label, Requires Diesel Exhaust Fluid, Air Conditioner, Cruise Control, Power Windows, Engine Brake, Detroit DT12-OA-1650 12-Speed Automated Transmission, Differential Lock, 12500 lb Front Axle, 40000 lb Rears, Dana DA-RT-40 Drive Axles, 3.08:1 Axle Ratio, 52500 lb GVWR, Air Ride Cab, 72 in High Rise Sleeper Cab, Bunk Beds, Thermo King TriPac Evolution Auxiliary Power Unit, Aluminum Outer Wheels, 295/75R22.5, Air Ride Suspension, 230 in Wheelbase, Air Sliding 5th Wheel, Dual Fuel Tanks