Meet the 2025 GMC Sierra 2500HD AT4, a heavy-duty powerhouse built for demanding work and serious capability. This Onyx Black truck combines professional-grade engineering with premium comfort and advanced technology. With the legendary Duramax 6.6L V8 Turbodiesel engine and 4WD capability, you're getting a truck engineered for towing, hauling, and off-road performance. - Duramax 6.6L V8 Turbodiesel with 10-Speed Automatic transmission - Gooseneck/5th Wheel Prep Package for heavy towing applications - AT4 Premium Plus Package with premium features and styling - 4-Wheel Disc Brakes with Electronic Stability Control and Brake Assist - Bose Premium 7-Speaker Sound System with SiriusXM and Apple CarPlay/Android Auto - Off-Road Suspension with 2-Speed Active Transfer Case and Hill Descent Control - Heated and ventilated leather front seats with 10-way power adjustments - Multicolor 15" Head-Up Display and HD Surround Vision with Trailer Cameras - Engine Block Heater, 220-Amp Alternator, and Heavy-Duty Battery - Body Color Wheel Arch Moldings and Spray-On Bedliner with GMC Logo This truck is equipped with the technology and safety systems you need for confident operation in any condition. The available Automatic Emergency Braking, Forward Collision Alert, and Trailer Side Blind Zone Alert work together to keep you secure. Premium details like the heated steering wheel, wireless charging, and remote vehicle starter add convenience to your daily drive. The Sierra 2500HD AT4 is ready for your next adventure. Visit us today to experience this exceptional truck and discover why it's the right choice for serious haulers and outdoor enthusiasts.