i have a 2001 5.4 supercrew and i get horrible gas milage. i only average 11 or 12 miles to the gallon. i have a si/do flowmaster exhaust and a k&n drop in air filter. i was wondering how to inprove my gas mileage. i have considered a performance chip. will that really help me that much? i can only go 300 to 315 miles to a tank of gas. thanks for the help because the gas is really eating my lunch. my dad had the truck and when i got my license he handed it to me. it has 130,000 miles on it if that makes any difference. thanks again for the help.

 

Your driving habits, a fresh tune up, and maintaining proper air pressure in your tires, have more to do with your mileage than anything you could do with a performance chip. I used to get about 12 MPG in town (commuting), and a little over 15 MPG on the highway, in my '02 5.4 Lariat SCREW 4x4. Be sure your MAF is clean (that K & N filter can cause you problems with oil getting on your MAF), and your electrical/charging system is in good shape.

 

How exactly are you calculating fuel economy. 300 miles per tank with a 25 gallon tank if you ran it dry is 12mpg. 300 miles per tank if you filled up when the low fuel light came on at 21mpg means you got 14.3mpg. You may not be getting as low FE as you think.

Regardless, 06 So Comfort nailed it. You will not get your money back back on any performance mods in fuel economy savings. Driving style will affect ifuel usage more than any other factor. Now, you do have a 130k mile truck. Cleaning the MAF with electronic parts cleaner, new fuel filter, injector cleaner, and spark plugs may help get another mpg or 2. 300-315 miles per tank seems quite reasonable for your truck, even if it were brand new. I truely get 11-12mpg which is more like 250-280 miles per tank when I fill up a little after the low fuel light comes on.

 

thanks for the help. i will clean my MAF and see if that helps.

 

K&N and MAF do not always work well together. I would ditch the K&N. Be very careful cleaning the MAF, they are pricey to replace. 20 inch rims don't help. Keep it under 2000 rpms. Don't waste your $ on a chip.

 

Drive these truck's easy and they do a lot better than the old truck's. My first Ford was a 1984 XLT reg. cab with 8' bed. 302 carb. engine, C-6 trans. it only got 10 city and if lucky 14 hwy. My 2004 Screw 5.4 4x4 get's consistent 14 city and up to 18 hwy. Key on hwy to cruise at lowest practical rpm's, I keep mine at 17 to 1800 rpm's.

 

run air pressure at max psi. may net you a mpg.... 38 is ok I would hesitate to go above 40 unless your tires can accept that high psi, but it could really hurt handling. maybe others with aftermarket titres can chime in - or post in tires section.