I've had my 2008 for about six weeks now and have about a thousand miles on it. I've checked fuel mileage twice, getting 16. 2 and 16. 8 hand calculated with mixed driving but more highway than not. . The overhead readout showed 20. 0 mpg on the 16. 8 calculation, so I won't put much faith in that. I was wondering what sort of highway mpg people with several thousand miles on the truck are getting. Thanks.