[ob_1jr]

have you changed your fuel filter since you bought it? You may not like it, but try driving no faster than 60 or 65 and see if it helps your mileage. I get about 10-14 mpg towing a 24' enclosed snowmachine trailer (car hauler) with 4 mountain sleds in it. that is winter and mountain driving. In the summer, I get 17-19 empty driving about 70 mph (that is 2000 rpms for me). With all the new emissions stuff on the new trucks and ULSD, that could be causing it your low mileage. I have a first generation engine, so I have a totally different animal than you. Very few people see the 20 mpg mark that I have often heard. The best I ever got with mine was almost 21 with stock tires on. Right now with the winter driving and super cold temps(-20 to -30F) up here, I saw 12 mpg unloaded going to fairbanks and back to eielson (about 25 miles one way). I did idle the truck for probably a total of 45 mins on this tank. I have heard that people are unhappy with the mileage they are getting on the new trucks. You might want to go to the dealer and see if there are any software updates for your truck. Other than that, I don't know what to tell you.