Detroit DD15 6 Cylinder 14.8 L Diesel 505 hp Engine, Engine Brake, Automated Transmission, Air Ride Cab, 34 in Flat Top Sleeper Cab, Aluminum Outer Wheels, 11R24.5, Airliner Air Ride Suspension, 234 in Wheelbase, Air Sliding 5th Wheel, Headache Rack, Dual Fuel Tanks