I know that this has been asked many a time..but i have noticed a few people recently posting about thier gearing experiece. My truck is on 35" BFG muds and has a 6" lift.I am torn between the 4.30's and 4.56's. Mathmatically the 4.30 would put me back to a stock 3.73 ratio while the 4.56 would be closer to an even 4. I'm not too woried about the RPM's on the freeway because i know that the V10 loves RPM. My best guess is about 2400RPM at 70PH with the 4.56s (right now i turn about 1950 with my 3.73's). Do ya'll think that there would be much of a difference in the MPG beween the two sets of gears? I do not tow that much, but i do A LOT of mountian driving and would like to keep the tranny from hunting (right now i just turn off OD).
Any suggestions would be great!

Thanks
FLYINFORD

 

Sounds to me like 4.56 is the way to go for you. Obviously you arent too concerned with MPGs or you wouldnt have lifted your truck. But to answer your question, no there wont be much difference in MPG between the 2 gearsets you have listed.