As for the showpiece of the Avalanche – the removable midgate that transforms the truck from passenger hauler to cargo mauler – GM designers pretty much left it alone, as it takes only minutes to fold the rear seats flat and remove the back window to expand the cargo bed. Once converted, the Avalanche goes from an SUV with a 5-foot 3-inch truck bed to a pickup with a bed that’s almost eight feet in length. Waterproof storage compartments in the sides of the bed stay the same, though the 2007 model does feature a lockable rear tailgate. The Avalanche also features removable and partitioned hard plastic tonneau covers that can be individually locked into place.