That mileage is terrible and I would not put up with it. Have had my '07 DCLB 4WD for about a month now and about 3800 miles so far. HAve logged every tank so far and am getting right at 19MPG avg. I drive a 77 mile each way trip to work through a forest and some good 2-lane roads running around 55-70 usually. Unless you are in the great white North and sucking up that Winter blend fuel that is definitely not "normal".