so im looking to put some 20x9s with a 275/65/20 tire on my new 2010 fx4 crew and im just wondering what kind of mpg it'll give me. anyone have a set up like that or have any experience with it that they could share?

right now, at 6500 miles, im averaging about 15 mpg. mostly highway but not taking it easy. best i had on all highway, keeping it under 65 the whole way was about 17. seems fairly normal for a fully loaded fx4 supercrew, right?

 

I just drove from NJ to Roanoke area, 485 miles each way. 2010 Screw FX4 w/18s that came with it and averaged 17.4 at 70mph and 18.3 at 65. This was why I am not changing them to 20s.

 

is that hand calculated or by way of the display?

 

I'd say hand our guys are seeing an average of 18 mpg on the highway (70+) with the anemic underpowered 4.6 3v in our crew cab 4x4s.

 

That was both, computer was about .3 higher. I also have 3.73s and 5.4l

 

so it looks like im probably still averaging a couple less than most. even with the 5.4 and 3.73s. anyone have any ideas what the 33s will do to that tho?

 

I've got that size tire on my 05. no discernable difference in MPG's from what I can tell. you've got an extra gear as well.

 

thanks slick. my local dealers got a customized f150 thats almost exactly like mine with the 20s and 275s and after seeing it i knew that would be my next mod. i measured them the other day at 33.5. with another inch or so(35s) costing a 2-3mpg loss i just wanted to make sure before i made the choice. now ive just got to find some f250 owners looking to sell their takeoffs.