I have had my 2010 LT1 4L AWD for a few weeks now and am loving it more every day. Here are the mileage logs calculated by refueling; first tank 25 mpg, second tank 26.88 mpg, Today total mileage is 1,254 tank was 15.84 gal and 451.7 miles = 28.5 mpg pretty impressive for a 3,925# vehicle. Driving is about 30/70 with the last tank being 15/85 city / HWY.