If not seafoaming it, then some lucas FI cleaner if the 4.9 is EFI. If you have a tonneau on, get rid of it. There's a vortex created in the bed of the truck that lets other air flow right over it, if you put a tonneau on, you're destroying that and destroying the mileage even more. Same with the mesh tailgates and whatnot. Dropping the truck would give more aerodynamics, but it would probably ruin the look, and going with the stock size tires instead of any aftermarket sizes you might have. Intakes probably won't help much, but if you had true dual exhaust it might.
Last edited by Mr.Distance; 12-25-2010 at 06:27 PM.