2026 GMC SIERRA 2500HD

2026 GMC Sierra 2500 HD AT4 Crew Cab 4WD, Duramax Diesel Power, AT4 Off-Road Capability, and Premium Heavy-Duty Comfort

If you’re searching for a GMC Sierra 2500 HD for sale in Ontario, a Duramax diesel truck near Bancroft, a heavy-duty 4x4 pickup with off-road capability, or a premium diesel truck built for towing, hauling, work, and adventure, this 2026 GMC Sierra 2500 HD AT4 Crew Cab 4WD is a serious truck with serious presence.

Finished in Onyx Black with a premium Jet Black and Kalahari interior, this Sierra HD AT4 delivers the bold, rugged look that truck buyers love, while still offering the comfort, technology, and refinement expected from a high-end GMC. The AT4 design gives it an aggressive off-road personality, while the heavy-duty platform gives it the strength needed for demanding work and towing.

Power comes from the legendary Duramax 6.6L V8 Turbo Diesel engine paired with a 10-speed automatic transmission. This proven powertrain is built for serious torque, confident trailering, long-distance hauling, and heavy-duty performance. Whether you’re towing equipment, hauling a camper, pulling a fifth-wheel, working on the job site, or heading into cottage country, this Sierra 2500 HD is ready.

Capability is a major highlight with a 2-speed active electronic Autotrac transfer case, automatic locking rear differential, trailer brake controller, Digital Variable Steering, Stabilitrak with trailer sway control and hill start assist, hitch guidance, hitch view, and the in-vehicle trailering app. The Gooseneck and 5th Wheel Prep Package further expands its towing potential for serious trailer owners.

The AT4 Premium Plus Package adds some of the most desirable comfort and technology features, including a power sunroof, rear camera mirror, multicolour 15-inch Head-Up Display, power sliding rear window, universal home remote, LED roof marker lamps, and dealer-installed off-road high-clearance steps. The Black Badging Package adds black GMC emblems and black badging for an even sharper, more aggressive appearance.

Inside, the Sierra AT4 is built to be both rugged and refined. Heated and ventilated front seats, heated second-row outboard seats, Adaptive Cruise Control, Bose premium audio, wireless charging, dual-zone automatic climate control, driver seat and mirror memory, heated wrapped steering wheel, premium floor liners, 120-volt power outlets in the cabin and cargo bed, and a 12.3-inch reconfigurable Driver Information Centre make every drive feel premium.

Technology is front and centre with the 13.4-inch GMC Premium Infotainment System featuring Google Built-In compatibility, navigation capability, wireless Apple CarPlay, wireless Android Auto, Bluetooth connectivity, SiriusXM, OnStar Basics, remote start, Bed View Camera, HD Surround Vision, and advanced trailering camera technology that helps make towing and parking easier.

The exterior is equally impressive with 20-inch high gloss black aluminum wheels, animated LED projector headlamps, LED fog lamps, LED cargo bed lighting, rain-sensing wipers, power folding and extending trailering mirrors, spray-on bedliner, rear wheelhouse liners, GMC MultiPro Tailgate, EZ-Lift power lock and release tailgate, and hitch area lighting.

Safety and confidence come from Sierra HD Pro Safety, including Trailer Side Blind Zone Alert, Rear Cross Traffic Alert, Driver Safety Alert Seat, HD Surround Vision, front and rear park assist, Automatic Emergency Braking, Forward Collision Alert, Front Pedestrian Braking, Lane Departure Warning, Following Distance Indicator, and IntelliBeam automatic high beams.

For shoppers comparing the GMC Sierra 2500 HD, Chevrolet Silverado 2500 HD, Ford Super Duty F-250, Ram 2500, or other heavy-duty diesel pickups, this Sierra AT4 stands out with Duramax diesel power, premium off-road styling, advanced trailering technology, heavy-duty capability, and a luxury-level interior.

If you want a diesel HD truck that can tow, haul, work hard, handle rough roads, and still deliver premium comfort every day, this 2026 GMC Sierra 2500 HD AT4 Crew Cab 4WD is built to do it all.

Available now at Boyer Chevrolet Buick GMC Bancroft.