Duramax 6.6L V8 Turbo Diesel and 4WD. In a class by itself! Real Winner! Do you want it all, especially low miles? Well, with this fantastic 2008 GMC Sierra 2500HD, you are going to get it.. Don't let the drumming of road noise wear you down. Bask in the quiet comfort of the cabin of this GMC Sierra 2500HD.