I have a 2004 5.4L FX4 Supercrew and am getting horrible mileage around 13-14 highway . I only have 2300 miles and im woundering if this is normal with the breakin or not .
Thanks

 

I don't know about the 04's but that's about all I'm getting with my 03, I'm at 17K now...

 

I average about 12 mpg city, and NEVER over 15.2 Hwy. Sounds like you are about average. This is a big topic on this board and there have been many posts regarding mpg. Bottom line, as heavy as these trucks are, you can't expect much better than where you are. I've heard of a few people with the smaller V8 engine getting better, but if you have the 5.4, it's pretty poor. I read a post not long ago that suggested we buy a Honda if we want 30 mpg!

 

That is about what my 03 gets as well. Dont expect much better out of it.

 

my FX4 screw w/ 3.73 i m getting about 17-18mpg HWY and approx 14.9 or 15.2 around the city.

Go and check 2004/2005 forum cuz some said to reflash PCM and it works for them to get better mileage gas and improve from throttle respone lack.

YOMAN!

 

I have never had an engine perform at its peak with less than 5k miles. 10k is more common in my experience. it should get a little better.

What kind of mileage are you expecting? At 80mph, I get about 13mpg. My best tank in 22k miles is 14.2mpg. Pushing a large brick through the air takes power.

 

Hmm, I guess the 4x4 does have a price and not just at the dealership. My 4x2 gets 14-15 around town and up to 20mpg on the highway. Then again that's using good premium gas without one of the 17 or so city blends. Living in a rural area does have some advantages. The cat back, SCT Tuner, and a drop in K&N air filter definitely helped me gain 3mpg on the highway but only .5-1mpg around town.

 

My 2004 Supercrew 5.4,4X4 has 2400 miles on it. The computer shows me 10.2 miles p/gallon. My Borla system brought it up from 10.1 mpg. lol....
I am going to try the superchip reprogramer next.

 

Totally agree with you there APT. My experience has been the same with the same mileage.

I can't quite figure out these guys claming to get 17-18-19 or higher with these trucks. Maybe they are calculating the mileage incorrectly?

 

Same thing with my 2003 F150 Screw.
I was shocked by the amount of gas this truck drinks compared to what I was used to with my old GMC 4.3 Vortec 6 cyl 5spd.

I use the wife's car to comute now.

Just last weekend I helped my brother move and pulled a 8X12 Uhaul trailer fully loaded. I hardly noticed it behind me (my brother had all IKEA funiture). The sticker on the trailer had maximum 45MPH ,but at 60 going up hill I could hardly feel the trailer. The only time I really felt it was returning it. When empty and no weight in it those Uhaul's really buck!

If you figured the gas milage on my trip with the trailer it would be about 9MPG. Although it would have taken 20 loads by car so even though the truck drinks about three times the amount of a car it still worked out that I saved some gas money.

 

Yes fuel economy is a big deal here!

We did a return trip to Florida last winter from Ontario Canada and the best MILES per US gallon that we got was 16.6. Travelling with the trafffic at about 75mph. God I love Imperial measure, only thing that makes sence!

4x4 S'crew Lariat - lots of toys
5.4 L
3:73 axle
17" tires
K&N drop in filter
45000 miles.

 

I have just run the first tank of fuel through my 2004 F-150 SCrew 4 X 4. It is a 5.4 with 3:73 and trailer towing package.
The only change I have made to the truck is that I have removed the inlet air "boot" from the inner fender including the flexible section, and installed a 10" conical filter at this location. All miles have been on the highway and I must say I was amazed as it got a whopping 17.4 mpg....I have used the cruise and have not exceeded 70 mph, and normally have it set on 65. Maybe I am just lucky, but I am happy thus far.

 

I just finished my first tank of gas on my new '04 CrewCab FX4 - 12.94 miles per gallon all city, stop and floor it driving. Can't say that I have had a chance to look at highway, but I am very happy with this mileage considering I was getting 8 - 9 miles per gallon with my '03 Lightning.

D-Day

 

The claims of 17-18-19 are accurate. I had a rental that got that. Now that I bought a new one, its very low. There is indeed a problem with certain 04 F150's. I just wish I could figure out how to fix it.

 

Will you post a couple of pics of your air tube mod? Do you still have the stock filter in the box or just the cone on the end?

If I don’t hot rod I get about 16mpg mixed driving but mostly local. I got a 2 wheel drive with a 3:55 rear.