Everything in balance. If you go for 4.10s or a lower ratio, your city mileage may increase slightly. However, you'll loose mileage at the top end. Can't have your cake and eat it too.

So how about some pics of that front end conversion?

 

Your lucky, with 6" of lift and 35" tires I get 9.6 mpg.

 

How are y'all getting such poor mileage? I have an 08 5.4L with stock gears, 6" lift, and 35s and I get like 12-13. And I don't drive slow at all.

 

I wish I knew the answer to your question. I bought it new and even with the 255's on it I've never gotten better than 13.

 

Hey kid, I don't mean to start a fight about the big O on your thread, but I started a thread for guys to do an octane experiment and report on it. It's not terribly scientific, but it does appear that the couple guys that tested it with me did get better mileage out of the higher octane fuel. It appears that the late model engines are able to advance the timing enough to make a difference.

My personal range is from 1-2 mpg better with 91 than 87. Try it for yourself and see if you think it makes a difference. Even if I've just subconsciously changed my driving style like some suggest, I've still saved a few bucks per tank.

Just to give you hope and maybe encourage you to try it, I drive an 05 XLT 5.4 SCrew.

Btw, didn't think about this, but I don't know much power that Edge has over the truck's computer, but it may not allow the truck to advance the timing. I don't really know. Like I said though, just give it a shot. You have little to lose by trying a couple tanks.

 

I have 2004 fx4 w 35x20 tires and 6 inch lift averaging 9.5 mpg . I went to 4.56 gears and immediately started getting 14 mpg and improved my towing big time.
It wasn't cheap to do but it was worth it to me.