No major changes for GMC's 2011 Sierra Heavy Duty, says Brenda Priddy, whose spy photo network grabbed these shots of a barely clad update. Priddy notes the new three-bar perforated grille shares styling with the 2010 GMC Terrain crossover. The eight-spoke wheels are also a new touch, but the rest of the bodywork and sheetmetal should continue looking like the current truck.

The Sierra and its corporate twin, the Chevrolet Silverado HD, will also feature an all-new chassis and a next-generation 6.6L "LML" Duramax V8 clean diesel engine. The 2011 Sierra HD pickup is expected to start production in the second quarter of 2010.

Photos copyright Brenda Priddy & Company. Reuse or reproduction without copyright holder's consent is prohibited.