2026 GMC Sierra 2500HD AT4

Vehicle Description

2026 GMC Sierra 2500HD AT4 Crew Cab 4WD for Sale in Mobridge, SD

Heavy-duty capability and off-road attitude come together in this new 2026 GMC Sierra 2500HD AT4 Crew Cab 4WD. It runs on a 6.6L V8 gasoline engine paired with an Allison 10-speed automatic transmission, while a 2-speed Autotrac transfer case, auto-locking rear differential and skid plates make the four-wheel-drive system ready for rough ground. Whether you are hauling across the ranch, pulling a camper to the river, or working through a Dakota winter, this truck is built for the job.

This AT4 is optioned for serious towing. The Gooseneck/5th Wheel Package adds stamped bed holes with caps and a 7-pin trailer harness, joining the trailering package, integrated trailer brake controller and power-folding, extending trailer mirrors. The Technology Package brings a Rear Camera Mirror and a multi-color Head-Up Display, and the AT4 Preferred Package adds a universal home remote, power sliding rear window and LED roof marker lamps. An engine block heater rounds it out for cold South Dakota mornings.

2026 GMC Sierra 2500HD AT4 Crew Cab 4WD — Stock #6W170

• Drivetrain: Four-Wheel Drive with 2-Speed Autotrac Transfer Case and Auto-Locking Rear Differential


• Engine: 6.6L V8 Gasoline


• Transmission: Allison 10-Speed Automatic


• Exterior Color: Sterling Metallic


• Interior: Jet Black with Kalahari Accents


• Packages: Technology Package, AT4 Preferred Package, Gooseneck/5th Wheel Package, and Trailering Package


• Towing & Trailering: Trailer Brake Controller, Vehicle Trailering App, Trailer Side Blind Zone Alert, StabiliTrak with Trailer Sway Control, 3.73 rear axle ratio, 10,850-lb GVWR, and dealer-installed Hitch Package


• Performance: Traction Select System with Off-Road and Tow/Haul modes, Hill Start Assist, skid plates, all-terrain tires, heavy-duty air cleaner, and red front recovery hooks


• Interior Comfort: 10-way power heated and ventilated front bucket seats, heated rear outboard seats, heated wrapped steering wheel, dual-zone climate control, driver seat and mirror memory, and 60/40 rear folding bench with storage package


• Technology: Premium GMC Infotainment System with 13.4-inch diagonal touchscreen and Google built-in compatibility, wireless Apple CarPlay and Android Auto, Bose premium sound, SiriusXM, 12.3-inch color driver info center, and multi-color Head-Up Display


• Safety: HD Surround Vision, Rear Camera Mirror, Automatic Emergency Braking, Front Pedestrian Braking, Forward Collision Alert, Lane Departure Warning, Rear Cross Traffic Alert, and Front and Rear Park Assist


• Convenience: Open and Start Remote Keyless, Universal Home Remote, Power Sliding Rear Window, 120V outlets in the bed and instrument panel, and engine block heater


• Exterior Highlights: GMC MultiPro Tailgate, spray-on bedliner, animated LED projector headlamps, LED fog lamps, LED cargo area and roof marker lamps, CornerStep rear bumper, plus dealer-installed off-road high clearance steps and black molded splash guards

Expert Insights

Reviewers at Kelley Blue Book and Edmunds point to the Sierra 2500HD's strong towing capability, upscale cabin and helpful trailering technology. The AT4 adds off-road hardware and a more rugged look, and this one's gooseneck prep, surround camera views and Head-Up Display put that capability to practical use.

Visit Beadle Chevrolet–GMC in Mobridge, SD

Come see this 2026 GMC Sierra 2500HD AT4 at Beadle Chevrolet–GMC in Mobridge, South Dakota. We serve customers from Aberdeen, SD, Bismarck, ND, and Pierre, SD — all within two hours. Call us at 605-845-7277 or visit beadleautogroup.com to schedule your test drive!