GMC Sierra 2011 Used In the name of God, the Most Gracious, the Most Merciful. There is a fully loaded 2011 GMC Sierra, a gem for the user. Gear, engine, chassis are guaranteed. Dial 4WD. The gear is 6-speed. Mileage: 400. The body has scattered paint repairs. The car's undercarriage has been completely overhauled. AC is icy cold. The highest offer reached 33.