3.0L V6 SIDI VVT and AWD. Don't let the miles fool you! Flex Fuel! 2011 GMC Terrain SLT-1 AWD. How inviting is this fantastic-looking 2011 GMC Terrain? This terrific GMC is one of the most sought after used vehicles on the market because it NEVER lets owners down. Named a 2010 Consumer Guide recommended Buy.