The 2011 Chevrolet Avalanche 1500 is available as a 4-door, 5-seat regular side. Starting at $36,300, the 2011 Chevrolet Avalanche 1500 LS 4x2 is powered by a 5.3L, 8-cylinder engine mated to an automatic transmission that returns an EPA estimated 15-mpg in the city and 21-mpg on the highway. The top of the line 2011 Chevrolet Avalanche 1500 LTZ 4x4, priced at $49,500, is powered by a 5.3L, 8-cylinder engine mated to an automatic transmission that returns an EPA estimated 15-mpg in the city and 21-mpg on the highway.