I have a 2012 manual Rubicon that I'm getting ready to put a 3.5 AEV lift and 35 inch Trail Grapplers on. I have a local shop ready to re gear but he is wanting to do 4.88's and I was thinking 4.56's.

I have been reading so many posts about this my eyes are crossed and I have one question I can't find. What will the 4.88's do to my Rubi in 4lo? Do I even have first gear anymore?

I don't really rock crawl I get on some down at the badlands in southern Indiana but I mainly off road up in Michigan around the National Forests. I have had to use 4lo when I got buried up in Michigan but not all that often really.

When I did use 4lo to get out I was running out of rpms very quickly so I can only assume it would be that much worse with the 4.88"s.

I have used 4lo in 3rd or 4th gear on some of the steeper logging roads up in the mountains too.

I also take two or three trips a year down to the cabin in the Smokey Mountains so it does see some highway travels.


Thanks

 

Sounds like 4.56's arE the right gears for you. Just tell your shop what you want.

 

There's no reason to run 4.88 with new motor. Try it out with your 4.10's first a lot of ppl run 37's with rubicon stock 4.10 and are completely happy. Might save yourself $1000-2000

 

Absolutely 10000000% no need to regear a 2012 + Rubi with 4.10s for 35" tires......especially with a manual.

 

I went with 4.88 and I'm glad I did worth every penny

 

I have a 2012 JK with 35s and 4.10 is great. Still a good daily driver but I'm off road pretty much every weekend. Try it before rehearing, the 3.6 has plenty of juice for 35s.

 

I also have the Trail Grapplers and 35's with an auto.

I am going to 4.56 as the tires are heavy and interstate driving, don't do much, is terrible.

Use of the cruise anytime is tough as it swings +-5 trying to stay at speed with my 3.21's.

Yea, the RPM at 80 will be a little high, but I don't do that much and the around town will be much better as well as on the trails.

With your Rubi, 4.88 would be way to slow, but unstoppable....

My 3 cents, took me a while to decide on 4.56 as it drove great with BFG AT's in 35 and didn't need the re-gear.

With more tire and traction, I am making the jump.

 

I ran my stock 4.10 gears with 35" tires on my 2012 JKU Rubicon auto. I didn't have any problems with that combo.

When I decided to get 37" tires, I changed to 4.56 gears. I ran the 4.56 gears with the 35" tires for a while and it was still good. My mpg went down a little going from 4.10 to 4.56 with the 35" tires, but not significant.

I'm now running the 37" tires with the 4.56 gears and everything is going great. If I lived in the mountains or at altitude, I'd get 4.88 gears for the 37" tires, but where I live in Texas, 4.56 works good, especially when the Interstate speed limit hits 80 mph.

I wouldn't go over 4.56 gears with a 35" tire. If you are paying someone to do your gears, consider the chance that you might go to a larger tire in the future so you don't have to pay for another gear change when you get the larger tires. The 4.56 gears work for both 35" and 37" tires. I think that the 4.88 gears are too much for 35" tires though.

 

Thanks for the replies. I appreciate the help.