Cummins ISX15 6 Cylinder 15 L Ultra Low Sulfur Diesel 400 hp Engine, 2011 US EPA Label, Requires Diesel Exhaust Fluid, Air Conditioner, Cruise Control, Engine Brake, Eaton Fuller RTOCM-16909A 9-Speed Manual Transmission, Differential Lock, 12000 lb Front Axle, 36000 lb Rears, Spicer DSP40 Drive Axles, 3.42:1 Axle Ratio, 48000 lb GVWR, Air Ride Cab, 72 in High Rise Sleeper Cab, Bunk Beds, Aluminum Outer Wheels, 295/75R22.5 Front Tires, 295/75R22.5 Rear Tires, Paccar Air Ride Suspension, 228 in Wheelbase, Air Sliding 5th Wheel, Dual Fuel Tanks