2026
GMC SIERRA 3500HD AT4 4X4 CREW CAB 6.75 FT. BOX SRW

The 2026 GMC Sierra 3500HD AT4 is built for those who demand unstoppable capability wrapped in rugged, premium craftsmanship. With its bold AT4 attitude, diesel-powered muscle, and advanced trailering technology, this heavy-duty truck is engineered to conquer demanding worksites, remote backroads, and everyday challenges with complete confidence. 

Performance & Capability 

• Duramax 6.6L Turbo-Diesel V8 delivering immense torque, long-distance durability, and refined power 

• 10-Speed Automatic Transmission engineered for smooth torque delivery and confident towing 

• Autotrac 4WD with Two-Speed Transfer Case for on-demand traction in snow, mud, rock, or gravel 

• AT4 Off-Road Suspension with skid plates, hill descent control, and increased ground clearance 

• 3.42 Rear Axle Ratio for balanced pulling power and stability under load 

• Heavy-Duty Cooling Systems: transmission oil cooler, engine oil cooler, diesel exhaust brake, and air filtration monitor 

• Trailer-Ready: integrated trailer brake controller, Hitch View, Hitch Guidance, and trailering app with camera provisions 

• Gooseneck / 5th Wheel Prep Package for maximum heavy-haul capability 

• Dual 120V Outlets (bed & cabin) plus a high-output 220-amp alternator for jobsite and adventure readiness 

• FlexRide Mode System tailoring throttle, steering, and traction response to terrain or driving style 

Winter & Weather Comfort 

• Heated & Ventilated Front Seats for comfort in any season 

• Heated 2nd-Row Outboard Seats to keep everyone warm in cold weather 

• Heated Steering Wheel for added winter comfort 

• Remote Vehicle Start to pre-warm or pre-cool the cabin 

• Dual-Zone Automatic Climate Control with rear vents and reinforced heating/defrost system 

• Engine Block Heater for reliable cold-climate starts 

• Winter Grille Cover to maintain optimal engine temperature in harsh winter environments 

Interior Comfort & Convenience 

• Premium Jet Black/Kalahari Interior with colour-keyed carpeting and removable-insert floor liners 

• Front Bucket Seats with power driver and passenger adjustments plus memory settings 

• Power Sliding Rear Window and Rear Seat Storage Package for added versatility 

• 13.4" GMC Premium Infotainment System with Google Built-In and wireless phone projection 

• 12" Reconfigurable Digital Driver Display plus 15" Multicolour Head-Up Display for real-time, customizable information 

• Bose Premium Audio System delivering rich, detailed sound 

• Wireless Charging, multiple USB ports, and in-cab 120V outlet for seamless connectivity 

• Keyless Open & Push-Button Start for effortless entry and ignition 

• Power-Retractable Assist Steps with LED Lighting for easy cabin access day or night 

Safety & Driver Assistance 

• Sierra HD Pro Safety for advanced protection in every drive 

• Forward Collision Alert with Automatic Emergency Braking and Front Pedestrian Braking 

• Lane Departure Warning and Following Distance Indicator 

• Rear Cross Traffic Alert and Trailer Side Blind Zone Alert for trailering confidence 

• HD Surround Vision, Rear Camera Mirror, and Bed View Camera for full-around awareness 

• Front & Rear Park Assist plus Seat-Mounted Safety Alert Seat 

• Adaptive Cruise Control for more relaxed highway travel 

• Teen Driver Mode, Buckle to Drive, and rear seat belt reminders for added safety awareness 

Exterior Styling & Utility 

• Exterior Colour: Titanium Rush Metallic — bold, modern, and unmistakably athletic 

• 20" Black Aluminum Wheels wrapped in LT all-terrain tires for a commanding stance 

• LED Headlamps, Fog Lamps, and Cargo Bed Lighting for maximum visibility in all conditions 

• Red Front Recovery Hooks and AT4-exclusive dark accents for rugged style and real capability 

• GMC MultiPro Tailgate offering loading flexibility, step access, and workstation functionality 

• EZ Lift Power Lock & Release Tailgate for effortless operation 

• Spray-On Bedliner and Bed-Mounted 120V Outlet for durable, work-ready versatility 

• Rear Wheelhouse Liners and underbody skid plates for added protection 

• LED Roof Marker Lamps emphasizing its heavy-duty presence 

• Trailering Mirrors with power adjust, heat, task lighting, and auto-dimming capability 

Whether you're conquering steep backcountry trails, hauling serious equipment, or embarking on weekend adventures, the 2026 GMC Sierra 3500HD AT4 delivers the perfect blend of off-road capability, diesel strength, and premium refinement — built for drivers who live boldly and work even harder.