Not Looking to start an argument,
just looking to gain knowledge and see what peoples opinions are on overall setups. I think this could be a great learning tool for new and old jeepers.

My 2007 Jk 2 dr had a stock dana 30 front and Dana 44 rear running 37s on a 4.10 gear ratio. Im aware that 37s are a little bit much to ask out of a dana 30, but I put this puppy thru hell and back...changed diff fluid every 10k checking it, and was perfect.

Traded that jeep in, got a 2014 JKU sport also dana 30 and 44 stock axles with a 3.21 Gear ratio... surprise, I just bought 37s...not yet mounted...afraid to see how they handle on the highway and power with the lower gear ratio,

ive been looking into re-gearing, is it necessary to go to a 4.10 ....4.88....5.13... what would you do, what have you done... what advise/knowledge can you share with me, a younger fellow jeeper.

Thanks
Jason


What Works, What Doesn't

any and all input appreciated.

 

Well if it was me and I am doing this when funds allow. I will be going with 4.56. Running 35's with factory 3.73 and its mostly doable but want 4.56

 

Click on the link below and scroll down to the charts for 2012+ JKs, and look at the chart that has your transmission type.

https://www.jk-forum.com/forums/modi...17/#post211276

 

4.56 and 4.88 are popular choices with the new 3.6 engine. 5.13's if you do a lot of crawling. I'm personally putting in 4.56's for 35's. Tons of opinions on here though, good luck!

 

I have 4.88's with 35" tires. I love the way it is now. Still have to downshift to 5th going thru the mountains to maintain 70mph here in san diego. I had 3.21.

 

With 37's you"ll want 4.88 min. to regain the factory torque curve. U can go more if U offroad alot(5.13)
& yes w/ 37" tires it is necessary to re-gear. ;-)