Vortec 6.0L V8 SFI High-Output, 4-Speed Automatic HD with Overdrive, and AWD. Pure power! Hard to find! Imagine the envy in your neighbors when you roll up to your driveway in this sizzling 2005 Chevrolet Silverado 1500. When H20 starts showing up in the weather forecast, you'll appreciate the AWD power delivery that helps you take control of the elements. New Car Test Drive called it '...a strong, rigid platform. It is, as the advertising tagline says, like a rock...'