Chevrolet & GMC are the same company and the same manufacturer. Infact, all GMC Sierras and Chevy Silverados have the SAME engine, the same transmission, and the same body style and parts. The only difference is some slight and minor interior details, and the front grill and bumper. They are both the same price range, and are both exactly compatible when it comes to comfort, handling, and power.

Ask any GM salesman, he'll tell you the same thing.

I own both Silverado 2500HD, and Sierra 2500HD.

Moe.