The Sierra HD?s Hollywood style and hard-working heritage make for a supremely capable pickup. The heavy-duty GMC and Chevy Silverado HD are twins separated at birth and share much of their sheetmetal and the available Duramax diesel and Allison transmission combo. The Duramax cranks out a class-leading 445 horsepower and a tremendous 910 lb-ft of torque. That allows the Sierra 3500HD to tow up to 23,300 pounds, which still trails the strongest Ford and Ram rivals. However, the Sierra has more civilized road manners. The Sierra HD ratchets up refinement in its top Denali trim, which is clad in chrome and gentrified with a premium interior. Although it?s not as high-tech as the Ford F-series Super Duty, the slick GMC looks better and works just as hard. READ MORE ??
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