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Discussion Starter #1
I have a 2013 jk running 35 inch tires and 3.21 gears... would it be worth my time to swith to 3.73's? I dont wanna do 4.10's because i do a lot of highway driving but the 3.21's make 6th gear useless
 

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Discussion Starter #2
Also i forgot to mention i may have a chance to get the 3.73 ring and pinions at a decent price
 

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Im at 3.21 with 33s and its a dog, but tolerable. If youre gonna regear you might as well go 4.10 or 4.56. Even at a decent price i dont think itd be worth it to go to 3.73. just IMO though.

Fellow pittsburgher here :)
 

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Just re geared a '14 stick JKUR to 4:56 from 4:10 to make my 35s tolerable. Better performance now than when it was stock.

Phil
 

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Do you know whats its like to change them? If i can get the 3.73s for 2 to 3 hundred bucks and change em in a day... i was thinking it would be worth it until the jeep is no longer my dd... fy i bought it june 28th of 13 and it sits now with 34k so i do A LOT of driving
 

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Im at 3.21 with 33s and its a dog, but tolerable. If youre gonna regear you might as well go 4.10 or 4.56. Even at a decent price i dont think itd be worth it to go to 3.73. just IMO though.

Fellow pittsburgher here :)
^^^Agree!!!!!!!!
 

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Do you know whats its like to change them? If i can get the 3.73s for 2 to 3 hundred bucks and change em in a day... i was thinking it would be worth it until the jeep is no longer my dd... fy i bought it june 28th of 13 and it sits now with 34k so i do A LOT of driving
Gears need to be adjusted for proper backlash... They are not something you unbolt swap over put the bolts back in and call it a day. it's something you find a reputable shop and pay them to do the install which a believe most shops quote around 8 hours labor for the pair. If you regear go at least 4.56 to make it worth the cost
 

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I'm currently running ~35's (315/70 r 17) with 3.73s and never see 6th gear on the freeway. I plan to go to 4.56 or 4.88 as soon as I can scrape together the cash.
 

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You could probably get 3.73 takeoffs real cheap, but the cost factor isn't the parts, it's the labor. You need to drive a jeep with 3.73's and 35s. I think the 3.73 is tolerable until you get the 4.56s
 

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Yea I wouldn't go swapping in used gears. As mentioned carrier preload, pinion preload are set with shims. If there's any wear in the gears, it's going to be harder to achieve a good pattern.
Setting up differential gears doesn't look hard but meticulous without the skill and proper tools ie indicator, press, micrometer, possibly a case spreader, etc.
 

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My Jeep 3,6l factory was 3.73 gear with wheels 35.12,5 very bad riding, acceleration was bad! But after installing the 4.56 gears was to go see as YouTube. But on the highway, the engine speed is a tall. I would advise you to put your case 4.1 assists.

IMG 7291 - YouTube
 

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Discussion Starter #13
Is there a sticky on the regearing procedure? All tools required and what to do?

I'm thinking that I'm gonna go with 4.10's brand new with install kit but I'd prefer to do it myself with the help of my dad who has experience with Dana rear ends from older Mopars.
 

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Is there a sticky on the regearing procedure? All tools required and what to do?

I'm thinking that I'm gonna go with 4.10's brand new with install kit but I'd prefer to do it myself with the help of my dad who has experience with Dana rear ends from older Mopars.
I have yet to see any how to's on regearing, probably because not many attempt this themselves. In my opinion if you don't know what tools you need or what to do you probably should leave it to the professionals. Proper tools and knowledge are key to a job like this, it can be very time consuming and fiddly even for those who know what they're doing
 

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Is there a sticky on the regearing procedure? All tools required and what to do?

I'm thinking that I'm gonna go with 4.10's brand new with install kit but I'd prefer to do it myself with the help of my dad who has experience with Dana rear ends from older Mopars.
If your Dad has changed out R&P, and set up Diffs in the past, then he will know what is required, including tooling.

This is a job for a professional, and not a Amateur!!!!!!!
 

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Is there a sticky on the regearing procedure? All tools required and what to do?

I'm thinking that I'm gonna go with 4.10's brand new with install kit but I'd prefer to do it myself with the help of my dad who has experience with Dana rear ends from older Mopars.
The sticky that needs to be put up is that gearing is not for even the most accomplished shade tree mechanic. The JK pinions use crush sleves to set bearing preload and they require in excess of 2-300 ft-lb of torque to install. It's not something the home mechanic is prepared to do.

If you're in the position where you have to ask "how do I do it", you don't have the experience to do it right. Get a professional to do it.
 

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We did our own gear install. If your father has done many gear swaps then sure- do it yourself. Gears, while technical, are gears. But if he did one gear swap 10 years ago- then X2 on the above- pay a pro. It requires a lot of extra tools and it is pretty difficult.
But either way- don't bother w.3.73s. There is a lot of worry over gear selection- and for good reason. But the difference is small incrementally. It'll be better-but won't bring you back to you stock tire performance. And you're screwing around w/something that is critical- and easy to get wrong- for very little benefit. Pay the $$ for 4.10s and do it right. 4.10s are perfectly fine for highway- not sure where you got the impression they wouldn't be. There are many thousands of Rubi's on the road w/4.10s and 35s. For that matter I'll bet you can find a dealer nearby with one you could test drive. (Or even drive a JK w/3.21s and 3.73s to compare- doesn't have to be on 35s.) And the difference in MPG between 3.73s and 4.10s would be a tiny blip.
 
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