Cummins ISX12G 11.9 L Compressed Natural Gas (CNG) 400 hp Engine, 15614.6 Engine hrs, Air Conditioner, Cruise Control, Power Windows, Engine Brake, Allison 4000RDS Automatic Transmission, 12000 lb Front Axle, 34000 lb Rears, 4.33:1 Axle Ratio, 46000 lb GVWR, Air Ride Cab, Aluminum Wheels, 295/75R22.5 Front Tires, 445/50R22.5 Super Singles Rear Tires, Airglide Air Ride Suspension, 196 in Wheelbase, Air Sliding 5th Wheel