2026 GMC SIERRA 2500HD AT4

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

Built for the work and terrain the Dakotas hand out, this new 2026 GMC Sierra 2500HD AT4 Crew Cab 4WD pairs the Duramax 6.6L Turbo-Diesel V8 with the Allison 10-Speed Automatic and a 2-speed Autotrac four-wheel-drive transfer case. The Max Trailering Package adds a 3500HD frame, leaf springs, a 12-inch rear axle and gooseneck/5th-wheel prep, so it is ready for serious hauling from day one. Finished in Coastal Dune over Jet Black with Kalahari accents, it is equally at home on a ranch road, a job site or a long highway run across South Dakota and North Dakota.

Beyond the standard AT4 equipment, this truck adds the Technology Package with a rear camera mirror and multi-color head-up display, plus the AT4 Preferred Package with a universal home remote, power sliding rear window and LED roof marker lamps. Dealer-installed off-road high clearance steps, a hitch package and black molded splash guards round it out. Inside, the 2026 GMC Sierra 2500HD AT4 delivers a 13.4-inch touchscreen, Bose premium sound and heated and ventilated front seats.

2026 GMC Sierra 2500HD AT4 Crew Cab 4WD — Stock #6W136

• Drivetrain: Four-Wheel Drive with 2-Speed Autotrac Transfer Case and Auto-Locking Rear Differential
• Engine: Duramax 6.6L Turbo-Diesel V8
• Transmission: Allison 10-Speed Automatic with 3.42 Rear Axle Ratio
• Exterior Color: Coastal Dune
• Interior: Jet Black with Kalahari Accents
• Packages: Max Trailering Package, Technology Package, and AT4 Preferred Package
• Towing & Trailering: Max Trailering Package (3500HD frame, leaf springs, 12-inch rear axle, shock package, gooseneck/5th-wheel prep), Trailering Package, Integrated Trailer Brake Controller, Trailer Side Blind Zone Alert, Vehicle Trailering App, Hitch Package, and 11,750-lb GVWR
• Performance: Traction Select System with Off-Road and Tow/Haul Modes, Skid Plates, All-Terrain Tires, Heavy-Duty Air Cleaner, StabiliTrak with Trailer Sway Control and Hill Start Assist, and Red Front Recovery Hooks
• Interior Comfort: 10-way power front bucket seats, heated and ventilated front seats, heated rear outboard seats, heated wrapped steering wheel, dual-zone climate control, driver seat and mirror memory, 60/40 rear folding bench with storage package, and premium floor liners
• Technology: Premium GMC Infotainment System with 13.4-inch touchscreen and Google built-in compatibility including navigation capability, wireless Apple CarPlay and Android Auto, 12.3-inch color driver information center, multi-color head-up display, Bose premium sound, SiriusXM trial, and 8 years of OnStar Basics
• Safety: Automatic Emergency Braking, Forward Collision Alert, Front Pedestrian Braking, Lane Departure Warning, HD Surround Vision, Rear Camera Mirror, Rear Cross Traffic Alert, Front and Rear Park Assist, and IntelliBeam
• Convenience: Open and Start Remote Keyless, Universal Home Remote, Power Sliding Rear Window, and 120V outlets in the bed and instrument panel
• Exterior Highlights: GMC MultiPro Tailgate, spray-on bedliner, animated LED projector headlamps, LED fog lamps, LED cargo area lighting, LED roof marker lamps, power-folding/extending heated trailering mirrors with auto-dim, CornerStep rear bumper, and off-road high clearance steps

Expert Insights

Reviewers at Kelley Blue Book and Edmunds consistently point to the Sierra HD's Duramax and Allison pairing for its effortless towing muscle, along with a well-finished cabin and smart trailering technology. The AT4 builds on that with real off-road hardware like skid plates, all-terrain tires and recovery hooks, and this truck's Max Trailering Package makes it an especially capable heavy-duty choice.

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!