A Free CARFAX for this vehicle is available at mercedesfarmington.com, where you can view the vehicle history report, ownership history, and maintenance reports. GMC Sierra HD AT4X is a bold, purpose-built pickup engineered for drivers who want serious capability with premium confidence. Finished in the AT4X trim, this Sierra HD delivers rugged 4WD/4-Wheel Drive/4x4 performance and is powered by a 6.6L V8 diesel engine, giving it the strength needed for demanding work and weekend adventure alike. Its commanding presence is matched by advanced safety and driver-assist technology, including Blind Spot Warning, Forward Collision Warning, Lane Departure Warning, Lane Keeping Assistance, Adaptive Cruise Control, Crash Imminent Braking, Dynamic Brake Support, Pedestrian Automatic Emergency Braking, Rear Cross Traffic Alert, Parking Assist, and a Backup Camera. Standard features such as ABS, ESC, Traction Control, Keyless Ignition, Daytime Running Lights, LED headlamps, and Direct TPMS help support everyday confidence. The Sierra HD AT4X blends durability, capability, and modern convenience in a highly capable heavy-duty pickup designed to stand out on the road and on the job. Mercedes-Benz of Farmington is proud to be recognized as a 2025 CarFax Top Rated Dealer.