2026 GMC Sierra 3500HD

Condition New

Transmission Automatic

Drive Train Four-wheel Drive

Trim AT4

Engine Diesel
6.6-L V-8 OHV 16V Turbo Diesel

Window Sticker

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Vehicle Summary

Meet the 2026 GMC AT4 — rugged capability wrapped in premium style. Dressed in a sleek black interior, this AT4 pairs serious off‑road hardware (lifted suspension, skid plates and all‑terrain tires) with a refined cabin, modern infotainment and advanced driver assists for comfortable daily driving and confident weekend adventures. Plus, it’s backed by comprehensive Basic, Powertrain and Rust warranties for added peace of mind — the perfect blend of performance, comfort and protection.