Ok sorry if this is in the wrong section. I am running 35"Procomp MT's, stock 4.10 gears with an auto and Im getting around 10-11MPG thats going off the comp. I get around 250miles to a tank. I can't leave it in OD or it will constantly kick me in and out. If I went with 4.88's will this help out since 4.56s would be me one over stock w/the 35's. Please tell me your thoughts..

 

4.88 will be better than 4.56, but 5.13 will be better than 4.88... get the 5.13.

 

5.13 is my next step. I have 35" and from what i gather with the math i am getting around 13.3 mpg.

 

Going with 4.88's would help you out a little and probably reduce the downshifting. You mentioned that you are going by the reading on the comp. The value it is giving you is incorrect, b/c the comp does not factor in the difference between your factory tire size and the 35's. The best way to see what you are actually getting is to just do the math.

 

here is something to think about:

http://www.quadratec.com/jeep_knowle...article-26.htm

cheers!