[escondidotundra]

not sure about this, but I don't believe your fix is here yet. You need to re gear the rear end. front dif if you are 4x4. I don't think they make gears yet. When they do, get a set that are a little more aggressive than stock and you will see your mpg raise at least enough to notice.

like an above post said, re calibrate the speedo. do that asap, at least it will shift where it is supposed to, that will help, but not like re gearing.

good luck