New 2026 GMC Sierra 3500HD AT4

• Heavy-Duty 4-Wheel Drive (4WD) system for rugged capability

• Off-Road Suspension Package with twin-tube Rancho® shocks & skid plates

• Durable all-terrain tires and bold AT4 styling

• Powerful engine options including available Duramax® 6.6L Turbo-Diesel V8 with high torque output

• Crew Cab configuration with spacious seating

• Premium GMC Infotainment System with 13.4″ touchscreen

• Apple CarPlay® and Android Auto™ compatibility

• Adaptive Cruise Control and advanced trailering tech

• Up to 14 available camera views including HD Surround Vision

• Trailer-aware tech and ProGrade® Trailering System available

• Heated and ventilated perforated front leather seating

• Keyless entry and push-button start

• Spray-on bedliner and practical cargo solutions

• Available Head-Up Display and premium packages

The 2026 GMC Sierra 3500HD AT4 is a heavy-duty powerhouse engineered for serious work, rugged off-road capability, and confident performance in demanding conditions. Built on GMC’s proven heavy-duty platform, the Sierra 3500HD AT4 blends strength, advanced technology, and refined comfort into a truck that’s equally at home on the job site, trail, or highway.