I have a 2000 sport 4x4 auto which I just put a 2006 block and heads out of a total that only has 42,000 miles on it but nomatter what I do I can't get anymore than 14mpg HELP (p.s stock tire size)

 

what size motor? my 99 was rated 14 city 19 hwy.

 

3.0l beast

 

Mine's down to 11mpg... oddly, yesterday on a 200 mile trip, it got 16.4mpg. Both suck imfo.

 

drive as alow as possible off the line is where it really matters

 

thing got 18 mpg yesterday... amazing. I think the thing has some issues. Some days it runs like a bat out of hell, other days it idles funny and stumbles during acceleration. It's a moody bastard.

 

sounds like a 3.0L to me lol

 

Check - Plugs, Airfilter, Fuel Filter, Oil In Everything Including Axles, Tire Pressure, And make sure your Cats are not clogged as that will cause Major fuel mileage loss and power loss

 

Plate the bottom with aluminum if you are that worried about MPG's. Make it as streamlined as possible, its a truck if you wanted fuel economy should have bought a prioos

 

mine is a 98 ranger 4.0 4x4 with a 3 inch lift and slightly larger tires and i get 14.67 mpg. i can get about 261 miles on my trip odometer before the fuel gauge comes on. u guys think a tuner would help out a lot?

 

My 2008 XLT 4x4 (4.0L V6) (I know, not correct forum, but anyway)
Is supposed to get around 14mpg, which I think they are all rated for. If you think 14MPG is not good enough on a Ford Truck, you may have not planned this out properly. 14 MPG for a truck owner is like being offered a position in heaven next to God, I only get around 12.9MPG and I have a heavy foot.
Best Tips:
Do not modify the engine, timing, cams, exhaust, intake, or anything else
Do not use power programmers
Do not use those fake fuel magnets
Do not use fuel savers

My best use of fuel saver, and it saves only little per tank, is the STP Fuel Injector Cleaner and STP Fuel Treatment. Also works well is Seafoam.