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2025 GMC SIERRA 2500HD DENALI 4WD 6.6L DURAMAX DIESEL X31 OFF-ROAD 5TH WHEEL PREP SUNROOF BLACK 20s SUMMIT WHITE LANCASTER PA
This 2025 GMC Sierra 2500HD Denali 4WD is powered by the 6.6L Duramax V8 turbodiesel paired with the 10-speed automatic transmission. Finished in Summit White, this Denali has a great setup with the X31 Off-Road Package, Gooseneck/5th Wheel Prep Package, power sunroof, and upgraded black 20-inch wheels.
The 6.6L Duramax produces 470 horsepower and 975 lb-ft of torque, giving the Sierra HD massive low-end pulling power for heavy trailers, campers, equipment, or everyday highway driving. The 10-speed automatic keeps the Duramax in its powerband while providing smooth shifts whether the truck is loaded or empty.
The X31 Off-Road Package adds extra capability beyond a standard Denali, including off-road-focused hardware and Hill Descent Control. A 2-speed active transfer case gives you the flexibility of low-range 4WD when conditions get more demanding.
This truck is especially well equipped for towing. The factory Gooseneck/5th Wheel Prep Package makes it ready for larger trailers, while the Bed View Camera, Trailer Camera Provisions, trailer viewing software, HD Surround Vision, and Trailer Side Blind Zone Alert give the driver excellent visibility around both the truck and trailer.
Inside, Denali brings the luxury expected from GMC's premium HD trim. Forge perforated leather-appointed seating, heated and ventilated front seats, heated second-row outboard seats, Bose premium audio, wireless charging, remote start, and a power sliding rear window make this a comfortable truck for long days behind the wheel.
The bed is equally well thought out with a GMC spray-in bedliner, LED cargo lighting, 120-volt bed outlet, and rear wheelhouse liners. There's also a second 120-volt outlet inside the cab for powering accessories or equipment.
The exterior combines the signature chrome Denali grille with Summit White paint, smoked amber roof marker lights, and the upgraded black 20-inch wheels, giving this truck a more aggressive appearance than the typical chrome-heavy Denali.
For someone who wants a premium HD truck that can still be put to work, this is an excellent combination: Duramax power, Denali luxury, X31, 5th-wheel/gooseneck prep, advanced trailer cameras, sunroof, and upgraded black wheels.
See it today at Mark Martin Motors in Ephrata, serving Lancaster, Lititz, Lebanon, and York. Call or message us to check availability or schedule your test drive.