Re-gearing questions

[vonlupus]

Thanks for taking the time to help out.

I'm doing a gear swap in the near future, but have a ton of questions that I can't seem to get answered because I am getting confused on the google and so new to the gear swapping scene.

Have a 2013 Sahara JKU automatic with 3.21 gear ratio, but upgrading to 35's soon, so thinking 4.10, 4.11, 4.56 or 4.88.

Will be a daily driver doing city driving, some highway, but also driving NY->TX a few times a year, while doing some light over-landing, camping and fishing in precarious locations.

• What gear kit / install kits are compatible with my current 3.21 hardware? What isn't compatible and what would I need to purchase additionally?
• Do I need both front and rear done?
• Confused on what Dana 30/44 means in relation to changing gears from 3.21
• What is a ballpark price range for gear swap? Will be done in the North East US most likely.

Thanks and please feel free to provide any insight.

 

[BLACKJKU]

I can give you this much info:

You'll have to do front and rear axles
Definitely 3:21's are the wrong ratio for those big tires
From what i've been reading on this Forum 4.56 or 4.88 should be good
If your doing more city driving then highway or off roading then probably a 4.56 would be better.

 

[Chris]

What gear kit / install kits are compatible with my current 3.21 hardware? What isn't compatible and what would I need to purchase additionally?
This is a question for your gear installer. When you talk to them, they will set you up with the correct kit and take care of everything, so you don't need to worry about this.

Do I need both front and rear done?
Yes, you need to have both front and rear done at the same time.

Confused on what Dana 30 / 44 means in relation to changing gears from 3.21.
Those are what axles you have. You'll need gears that are compatible with your Dana 30 and Dana 44, as oppose to a Dana 44 / Dana 44 setup like on a Rubicon.

What is a ballpark price range for gear swap? Will be done in the North East US most likely.
$600 for parts and between $1000 to $1600 for labor. I've had three re-gears done on three Jeeps, and each time it was between $1600 and $1800 for parts and labor.

 

[vonlupus]

What gear kit / install kits are compatible with my current 3.21 hardware? What isn't compatible and what would I need to purchase additionally?
This is a question for your gear installer. When you talk to them, they will set you up with the correct kit and take care of everything, so you don't need to worry about this.

Do I need both front and rear done?
Yes, you need to have both front and rear done at the same time.

Confused on what Dana 30 / 44 means in relation to changing gears from 3.21.
Those are what axles you have. You'll need gears that are compatible with your Dana 30 and Dana 44, as oppose to a Dana 44 / Dana 44 setup like on a Rubicon.

What is a ballpark price range for gear swap? Will be done in the North East US most likely.
$600 for parts and between $1000 to $1600 for labor. I've had three re-gears done on three Jeeps, and each time it was between $1600 and $1800 for parts and labor.

tyvm! very informative

 

[vonlupus]

I can give you this much info:

You'll have to do front and rear axles
Definitely 3:21's are the wrong ratio for those big tires
From what i've been reading on this Forum 4.56 or 4.88 should be good
If your doing more city driving then highway or off roading then probably a 4.56 would be better.

+1 tyvm!

 

[Gobionecanobi]

quick question and hopefully someone has an answer. I just re-geared my 2018 jku to 4.88 front and rear with eaton posi front locker and eaton true locker on the rear. i have sent my jeep back to the mechanic at the dealership to fix the issue three times now and again this money it will be back. since the install, my jeep has decided to go into limp mode everytime i drive for about 20 or minutes. when i get to around 40mph the jeep will hit third gear, sometimes it will pass third gear like normal and other times it will not shift over that and then wont shift back down to first. it will just be stuck in third gear. when i put it in park i can hear a ticking noise as if its trying to find first gear but can. i turn the jeep off and restart immediately and the ticking noise is gone and the jeep will shift through all gears just fine for awhile. the computer has been flashed and the problem pursists. my mechanic doesnt know what to do anymore as well. ive called super chips to see if its on there end with the update and they say no my update went well and the jeep took it. so my computer keeps throwing codes where my engine light keeps going on and off. my code reader keeps telling me its a third gear sync problem. does anyone know what the issue could be?

 

[BLACKJKU]

It's because you can't have a locker in the rear with a auto trans because somehow it causes problems with it electronically. Read through this alot of info: https://www.google.com/search?biw=1...d=0ahUKEwiirtyLqrbpAhWCGc0KHcN_AWI4ChDh1QMICw

 

[Gobionecanobi]

It's because you can't have a locker in the rear with a auto trans because somehow it causes problems with it electronically. Read through this alot of info: https://www.google.com/search?biw=1...d=0ahUKEwiirtyLqrbpAhWCGc0KHcN_AWI4ChDh1QMICw

i love that i spent all that money and now come to find out its an issue. ill have to figure something out then. get an electronic locker for the rear. thank you for that helpful information

 

[BLACKJKU]

i love that i spent all that money and now come to find out its an issue. ill have to figure something out then. get an electronic locker for the rear. thank you for that helpful information

Sorry it couldn't have been better or cheaper news, main reason I went with a Manual trans.