Vortec 6.2L V8 SFI VVT Flex Fuel, 6-Speed Automatic HD Electronic with Overdrive, AWD, and Cloth. Crew Cab! Don't let the miles fool you! 2010 GMC Sierra 1500 Denali AWD. Tired of the same ho-hum drive? Well change up things with this fantastic-looking 2010 GMC Sierra 1500. Awarded Consumer Guide's rating of a Recommended Large Pickup in 2010. This superb GMC is one of the most sought after used vehicles on the market because it NEVER lets owners down.