Originally Posted by moabjk072d

I have 5:13's in my jeep and I don't have any noise from them, I havent had any problems so far with them and I really like the lower gearing. I have 35's and it seems I am pretty close to what my jeep was geared to stock.

Originally Posted by troyboy

my math shows that if the original tires are say 31.5" then going to a tire that is 35" would be 11% larger.

So 3.73 + 11% = 4.14
4.10 + 11% = 4.55

so why would a person with a 33" or 34" tire want to go 4.88 or higher???
I'm so confused

Originally Posted by JKDoc

I've spent hours with gear charts trying to decide on the perfect setup. Currie Enterprises has some neat tools on their website if you want to make your own. I'm going with 4.56 gears and 35s. I have the six speed. I don't care if I can't climb the mountains in 6th gear, that is why I have 3rd and 4th and why I ordered the manual. The actual ratios are very close to what you have with stock 4.10 and 32s. I agree the 2.72 transfer ratio can be too high if you are trying to do any rock crawling. I was able to climb Ken's Climb on Fins and Things in Moab with no problem but I think that was the limit. I did stall on a number of ledges. I'm taking care of this with an Atlas 4.3:1 2 speed case. By changing the transfer case I get a crawl ratio lower than a stock Rubi even with the 35 inch tires and still have road ratios that don't have my engine spinning its guts out at 65 mph.

The other reason to stay at 4.56 was the advice I received that the 4.88 pinion for the D30 was getting really small and could be a problem. I guess we have plenty of folks running these. I did not need to.