Question about economy

[99F350]

I have a 03 ext im about to make my DD. If I put efans, gut the cats, and a cold air along with a chip what kind of mpg gains can I expect? It has a 6.0 AWD and some damn 24s. Im getting about 14 to 14.5 now

[567234ta]

alot depends on driving style, my 96 with the 5.7 was getting 20+ on the highway with efans, full syn oil, k&n filter. so you should be able to get much better with a few mods like that. can you pull the front drive shaft on those awd?

[Weirdguy]

First I don't think 24's help your mileage, and my guess would be about 4 mpg with those mods... Other than gutting the cats, they're not as restrictive as they used to be. In fact some vehicles run worse with out them. Get a decent catback instead, and hit up ff_jeff for one of his HHO kits.

HHO kits

[GasGuzzler]

I have almost the same combo but with 17's. See my signature for mods. I get about 14 city and up near 16 highway. The mods helped a very small amount in MPG but a lot with usable power.

[99F350]

For the most part I obey the speed limits. It came with the 24s and it has a baer brake up grade so the stock wheels dont fit. I was hoping to squeeze 17mpg around town and about the same for hwy. I hope to get close to that with those mods.

[GasGuzzler]

Good luck.

[bangbangskeetskeet]

With the mods I have on mine I am getting an average of 17-18. I only have the 5.3 so that helps me a little. I drove all highway a few months ago and got 21. I have been running on 91 octane tho. I did notice that when I went from 87 up to 91 I got like a 1.5-2 mpg increase. I do have 16's too but my tires are 285's.
With a tune Im thinking I can squeez a little more out of it.

[99F350]

I could always turn it off when I go down hill and only drive with the wind. LOL....I also here right hand turns are more fuel effecient than left.

[txarkitekt]

I could always turn it off when I go down hill and only drive with the wind. LOL....I also here right hand turns are more fuel effecient than left.

LOL... That right hand turn thing is what couriers like DHL, UPS, and Fed Ex has implemented lately to help conserve fuel.
I would say to sell the 24s and get some smaller diameter and lighter wheels. Unsprung weight is at your disadvantage. What gears you running?
I would do efans, pulleys, LT headers, no cats, a decent catback exhaust, CAI and a live custom tune to get the max MPGs out of your truck. I had a 93 octane mail order tune that yielded me like 12 mpgs. But once I got a live tune, I am averaging 2o mpgs city/hwy mixed. I bet I can pull close to 22 on the freeway if I keep my cruising speeds areound 60 mph...

[99F350]

I don't care for the wheels much, but with the big brake kit stocks wont fit. I don't want to buy some 20s or something just to save a little weight. Plus they have brand new tires.