Jeep Wrangler Forum banner
  • Hey everyone! Enter your ride HERE to be a part of JUNE's Ride of the Month Challenge!

1 - 10 of 10 Posts

·
Registered
Joined
·
591 Posts
Discussion Starter · #1 ·
My 2015 JK Sport 2DR is 8 months old. I have the Dana 30 in the front and Dana 44 in the rear 3.21. I got a quote for $ 1700 for 4.88 Yukon parts. I have 34" Nitto's on now but may want 37" eventually. My issue is the factory warranty. I usually don't screw with major parts under the 3 year warranty so I am really torn on what to do.

Thoughts? Go for it and don't look back? Any insight would be appreciated.

Thanks
 

·
Retired Moderator
Joined
·
100,626 Posts
Only you can answer your question, because it depends on how satisfied your are with the current ratio and 34's. How long before you go with 37's is another question.

Yes, the 4.88 ratio is what you will need for 37's.

Most on the Forum, will tell you that, the 3.21 and 34 combo sucks. And then somebody else will jump in and say, I am running that combo and I am satisfied. So it really depends on your expectations..
If you are really unhappy with the current performance, then re-gear now!

As for the warranty, if you decide to go with the 4.88's, then make sure that your gear shop is experienced and get a copy of their warranty in writing!!!
 

·
Registered
Joined
·
1,099 Posts
Only you can answer your question, because it depends on how satisfied your are with the current ratio and 34's. How long before you go with 37's is another question.

Yes, the 4.88 ratio is what you will need for 37's.

Most on the Forum, will tell you that, the 3.21 and 34 combo sucks. And then somebody else will jump in and say, I am running that combo and I am satisfied. So it really depends on your expectations..
If you are really unhappy with the current performance, then re-gear now!

As for the warranty, if you decide to go with the 4.88's, then make sure that your gear shop is experienced and get a copy of their warranty in writing!!!
Agree with all above. As far as gears voiding your warranty, the burden of proof is on them to prove your mod caused the failure. I.E. with 35" tires, I did not even try to argue a warranty claim when my ball joints failed at 33,000 miles. No point, they could easily (and correctly) claim the tires were the cause. They'd have to prove your gears caused "X" issue.

I regeared to 4.56 from 3.21 on a JKU sport auto on 35's. The best money I have spent thus far on my Jeep.
 

·
Registered
Joined
·
990 Posts
I have a 2013 JK 6 speed and 5th and 6th gears were useless with 35's and 3.21 gears. I've gone to 4.88 gearing and while I sometimes feel I should have gone with 4.56 gears I am happy with the set up. IMO, I would use great caution running 37" tires on the stock D30 front diff. That's just me but I won't as I feel its asking for more trouble than they are worth.
 

·
Registered
Joined
·
591 Posts
Discussion Starter · #5 ·
I appreciate the comments. If it matters its an automatic and came from the dealer with the lift and the 34's so right now its on their dime if something on the drive line craps out.
 

·
Registered
Joined
·
1,713 Posts
I was in similar situation. Had 35" and 3:21 with front D30. It run ok.
Then i decided to move up to 37" while i still had warranty on the Jeep. Didn't want to spend a lot on D30 so i decided to get Prorock44. Then regeared 4:88 and it drives much better on 37" then 3:21 and 35" Duratracks i had before.

I'd say go for it. But be prepare to drop some money cause to run 37" you may need to add a few more expensive mods like new steering components(tie rod, drag link flip, SS, new driveshafts etc)
 

·
Registered
Joined
·
4,110 Posts
Re-gear, re-gear, re-gear. I respect and understand what Old Dogger says- but the difference is HUGE. I couldn't be happier with 4.56s from 3.21s. From street to trail. Mileage sucks but I don't care.
Well, mostly happy LOL. For 37s I'd go 4.88s.
X2 on warranty as mentioned per above. Don't wait 2 years.
 

·
Registered
Joined
·
837 Posts

·
Registered
Joined
·
591 Posts
Discussion Starter · #9 ·
1 - 10 of 10 Posts
Top