In many cases, yes. Compatibility of the 6.5′ truck bed of a 2011 GMC 3500HD is common with Chevrolet Silverado 2500HD and 3500HD of the same year. Since GMC and Chevrolet trucks are both part of General Motors, many body parts and mounting systems are very similar. Yet, it is never too late to check the very year range and the style of the body before installation. Checks should also be done on bed rails, tailgate fittings, wiring harnesses and mounting bolts. A lot of truck owners manage to exchange Sierra and Silverado HD models to exchange beds saving money and enhancing availability. Nevertheless, paint color and trim details can be different even in case the physical fit is right. Before buying, checking measurements and alignment of bolts to ensure they fit will prevent the problems of the installation and the extra costs in the future.