Previously posted in another forum, but so many errors and typos, I thought I would repost here and try for a response from the locals.
Here is my dilema. Quite simply, I seem to be getting lousy gas mileage. After a 300 mi round trip to So Maine yesterday, I determined I am only getting 10 mpg.
This eng is a newer rebuilt 4.9, (done in 03) with less than 10,000 miles. It is in an 89 F150, sb. 5spd, 4wd. (Rear axle ratio is 3.55) 31x10.5x15 tires.
I don't drive this hard at all. Avg 65 mgh, all highway, Am I expecting too much or should I be getting better mileage here? Is there an easy way to pin this down? Plugs, wires etc. Any advice will be appreciated.