The 2026 GMC Sierra HD: What We Like
Under the hood, the Sierra HD packs a serious punch. The standard 6.6L V8 gas engine delivers 401 hp/464 lb-ft of torque, but if you need even more muscle, the available 6.6L Duramax® turbo diesel engine is a beast. It generates up to 470 hp/975 lb-ft of torque and can tow up to 36,000 pounds1. Both engines come paired with an Allison® 10-speed automatic transmission to keep all that power in check.
