The standard 6.6L V8 gas engine produces 401 hp and 464 lbs.-ft. of torque. Paired with a 10-speed Allison® automatic transmission, it delivers smooth performance and confident capability for everyday hauling.

If you need maximum pulling power, the Duramax® 6.6L Turbo-Diesel V8 generates 470 hp and an impressive 975 lbs.-ft. of torque. The diesel's immense low-end power makes towing heavy loads feel remarkably effortless.

Properly equipped, Sierra 2500 HD models can tow up to 22,390 lbs., making them ideal for large trailers, equipment, RVs, and recreational toys frequently seen throughout Northern California. The Sierra 3500 can pull a max of 36,000 lbs. for those who need professional-grade capability.

Properly equipped, Sierra 2500 HD models can tow up to 22,390 lbs., making them ideal for large trailers, equipment, RVs, and recreational toys frequently seen throughout Northern California. The Sierra 3500 can pull a max of 36,000 lbs. for those who need professional-grade capability.

The available ProGrade® Trailering System enhances confidence through an integrated trailering app and up to 14 camera views like the innovative Transparent Trailer View. Hitching, maneuvering, and monitoring a trailer become significantly easier, even with substantial loads attached.

The Sierra HD's cabin scales impressively across the lineup. Best-in-Class standard Crew Cab front head and legroom set a high standard. Lower trims prioritize durability and functionality, while SLT and above introduce premium materials, improved seat comfort, and a quieter cabin environment. Trims like the AT4X and the lavish Denali and Denali Ultimate add exclusive detailing, authentic wood trim, perforated leather upholstery, and available 16-way power front seats with heating, ventilation, and massage. The result is an interior that functions equally well as a mobile office, long-distance cruiser, or family vehicle.

Technology plays a central role in the Sierra HD experience. Most trims feature a 13.4” touchscreen paired with a 12.3” digital driver information center. Wireless Apple CarPlay® and Android Auto™ come standard, and most trims are also equipped with ultra-convenient Google Built-in. Other available upgrades include a 15” Head-Up Display, Rear Camera Mirror, and Bose® premium audio.

Trailering technologies integrate seamlessly into the infotainment system, giving you access to trailer profiles, camera views, and towing information through a single interface.

The 2026 Sierra HD comes equipped with a comprehensive suite of driver-assistance technologies. Standard features include Forward Collision Alert, Automatic Emergency Braking, and Lane Departure Warning.

Available upgrades include HD Surround Vision, Adaptive Cruise Control with Trailering, Rear Cross Traffic Alert, Blind Zone Steering Assist with Trailering, and advanced camera systems that provide enhanced visibility while towing.

The Sierra HD Pro trim is a purpose-built work truck featuring durable materials, core trailering technologies, and Best-in-Class cargo bed volume.

SLE introduces a more modern experience with the 13.4” infotainment display, Google Built-in, 12.3” digital driver information center, and Traction Select with Tow/Haul Mode, improving day-to-day usability.

SLT brings a noticeable upgrade in comfort. Heated 10-way power front seats and a heated steering wheel are complemented by upgraded tech like the ProGrade® Trailering System with the In-Vehicle Trailering App.

The ferocious AT4 is off-road-ready, equipped with off-road suspension, Rancho® shocks, HD Surround Vision, Adaptive Cruise Control with Trailering, and all-terrain tires. Inside, unique Jet Black and Kalahari accents reinforce its adventurous character.

AT4X elevates off-road performance further with Multimatic® DSSV dampers, a factory lift, front and rear electronic locking differentials, and 35” mud-terrain tires engineered for challenging terrain.

Denali moves firmly into luxury territory with signature GMC styling, 20” Ultra-Bright machined aluminum wheels with bright chrome inserts, Denali-exclusive authentic wood, and Forge perforated leather seating with heating and ventilation.

At the top of the lineup, the lavish Denali Ultimate shows off a signature Vader Chrome grille, an exclusive Alpine Umber interior with Paldao wood and 16-way full-grain leather seats with massage. Its 12-speaker Bose® premium audio system with Centerpoint surround sound is accompanied by the MultiPro Tailgate’s Audio System by KICKER®.