2026 GMC Sierra 3500HD AT4

Experience commanding power and advanced technology in the 2026 GMC Sierra 3500HD AT4, designed for heavy-duty performance and off-road capability with premium comfort.

Built to handle the toughest tasks, this Sierra 3500HD features a Duramax 6.6L Turbo-Diesel V8 engine delivering 470 hp and an impressive 975 lb-ft of torque, paired with a smooth 10-speed automatic transmission and 4x4 drivetrain. The Gooseneck/5th Wheel Prep Package includes a hitch platform and bed-mounted 7-pin trailer harness, making towing large trailers effortless. Off-road adventures are supported by the Off-Road High Clearance step and body-colour wheel arch mouldings, while running boards and a bed liner add convenience and durability.

Inside, the AT4 Premium Plus Package brings luxury with heated and cooled leather bucket seats, power-adjustable driver and passenger seats with lumbar support, and seat memory. The cabin also benefits from a power sunroof and advanced technology including an aerial view display system, adaptive cruise control, blind spot monitor, cross-traffic alert, and lane departure warning for enhanced safety. Trailer tire pressure monitoring sensors and a remote engine start system add further practicality. With integrated turn signal mirrors, LED headlights, and fog lamps, this Sierra 3500HD is ready for any challenge on or off the road.