I've been having fuel mileage issues for a long time with my truck. About 54,000 miles or so, actually. Anyway, most of the time the truck is sluggish taking off and gets around 10-11 mpg. But, occasionally it will take off like it should and get around 17 mpg. This however doesn't happen often or for very long. Does anybody have any ideas, besides air filter and fuel filter, I've changed both, alot. Ive also replaced the MAF sensor. I have noticed that since the temp has been dropping here in Cheyenne it seems to run correctly more often. Sorry for the long post but I'm just trying to be as thorough as possible.