D13J425 6 Cylinder 12.8 L Ultra Low Sulfur Diesel 425 hp Engine, 2014 US EPA Label, Requires Diesel Exhaust Fluid, Air Conditioner, Engine Brake, ATO2612D Automated Transmission, Differential Lock, 12350 lb Front Axle, 38000 lb Rears, Meritor MT-40-14X Drive Axles, 2.64:1 Axle Ratio, 50350 lb GVWR, 295/75R22.5 Front Tires, 275/80R22.5 & 295/75R22.5 Rear Tires, Air Ride Suspension, 173 in Wheelbase, Air Sliding 5th Wheel, Auto Lube, Dual Fuel Tanks