Engine: A 6.6L Duramax Turbo-Diesel V8 engine with a 10-speed Allison automatic transmission Towing capacity: A maximum towing capacity of 18,500 pounds Payload: A maximum payload of 3,715 pounds Fuel efficiency: A combined 15 miles per gallon Trailering package: An available Advanced Trailering package with features like a pre-departure checklist, trailer tire pressure monitoring, and a tow/haul reminder Transmission: A 10-speed Allison automatic transmission, or you can choose a six-speed transmission Diesel Exhaust Fluid (DEF): The DEF fill is located in the fuel door Wheels: 20-inch 16-spoke aluminum wheels Sunroof: A power sunroof Driver seat: A 10-way power driver seat with power lumbar Satellite radio: SiriusXM satellite radio Air filter: A heavy-duty air filter with air filtration monitoring Oil coolers: External engine and transmission oil coolers Frame: A fully boxed high-strength steel frame Bed: A Durabed with 12 standard tie-downs Rear bumper: A CornerStep rear bumper Cargo area lighting: Cargo area lighting Trailering mirrors: Vertical trailering mirrors