Re-gearing for 35s (need some build advice)

The cost is high, but ask yourself if you want to learn (and intend on doing this again in the future). If you dont foresee other rigs needing gears done Id pay up. Gears are hard, take a lot of time to do right and require some special tools.

I did my own, but thats because I will regear other rigs in the future. Was worth the pain to learn.

I am really in no rush. I really don't have an excuse when there are SO many videos and guides detailing it. I think, for me, it's less about saving money and more about learning about my rig in particular. I am an engineer by trade so this is really just fun and interesting for me. Not a daunting task that needs to get done.

Feel free to screenshot this post LOL it might age really well
 
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Just an update for anyone interested. I had 2 shops nearby come back to me with quotes in the Denver/Castle Rock Area.

Double locker and re-gear with a super 35 kit is 5.4k from one shop and 5.5k from another 3.5k in parts 1.5k in labor. I intend on doing the work myself I just wanted to justify it. Maybe I will have to spin up a build thread to document it for folks that are interested in how a DIY re-gear holds up... HA

If you're interested in another quote check out Core Off Road in Castle Rock. My friend just had them regear his JL for $2,375. Granted that didn't include lockers. They also gave him a 2-year warranty. He was going to go 4.88 and they talked him into 5.13.
 
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If you're interested in another quote check out Core Off Road in Castle Rock. My friend just had them regear his JL for $2,375. Granted that didn't include lockers. They also gave him a 2-year warranty. He was going to go 4.88 and they talked him into 5.13.

Core and The Edge are the shops that provided me quotes. I didn't want to really name shops. They both wanted to talk me down from 5.13 to 4.88 or 4.56.
 
Exactly why I haven't pulled the trigger on gears yet. Still researching to see if what they said is actually an issue. Thanks!

It's a non issue. The deeper the gears are the mechanical advantage is further in favor of the pinion and the entire drivetrain. Everything requires less work to push the Jeep. You already know this when you ride a multi gear bicycle and it is easier to pedal in a lower gear.
 
the difference between 4.88 and 5.13 is minimal. id go 5.13 all day

NV3550 with 35" tires at 70 mph
4.88 = 2558 rpm
5.13 = 2689 rpm

Based on those numbers, an estimate on paper obviously with just numbers and no outside variables

0.01 of a gear amounts to 5.24 rpm with 35s at 70MPH
My 3.07 would be at 1609 rpm

This is going to be a huge jump for me
 
Based on those numbers, an estimate on paper obviously with just numbers and no outside variables

0.01 of a gear amounts to 5.24 rpm with 35s at 70MPH
My 3.07 would be at 1609 rpm

This is going to be a huge jump for me
You will never regret regearing to 4.88 or 5.13 for 35's with the 4.0 engine and 5-speed manual transmission. For those reading this in the future, you would regret regearing to only 4.56 for that combination.
 
Based on those numbers, an estimate on paper obviously with just numbers and no outside variables

0.01 of a gear amounts to 5.24 rpm with 35s at 70MPH
My 3.07 would be at 1609 rpm

This is going to be a huge jump for me

3.07 gears on the left and 5.13 gear on the right.

1701996844476.webp


3.07 on left and 4.88 on right

1701996946783.webp


Play with different gearing on http://www.grimmjeeper.com/gears.html
 
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Tha

That’s a long haul on the 405, I’m at the 710 & 405

yeah it’s definitely a ride. I switch the routes up a lot depending on sig alerts but I’ve been doing it so long that I’ve got all the routes dialed in for efficiency. I don’t even complain when there’s traffic since I just enjoy being in my rig.

It’ll all be even more enjoyable once the outboard is done
 
Core and The Edge are the shops that provided me quotes. I didn't want to really name shops. They both wanted to talk me down from 5.13 to 4.88 or 4.56.

5 speed? AX-15? And they want to talk you down. Even if it was the NV3550 that is crazy. They should try living with it with your transmission for 6 weeks. They'd be regearing it themselves to 5.13.

I can barely survive on 4.56 with 35's and the 6-speed. I should have 5.13's all the way. There is no question here, and I have no idea why they would try to talk you down. It is your Jeep. Do what is right.

Think about this. Are those guys Jeep enthusiasts and purists? Do they sit around 365 days a year reading people's experiences and learning from the best? Do they really know all they claim to know just because they are named "The EDGE"? Ridiculous.
 
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You will never regret regearing to 4.88 or 5.13 for 35's with the 4.0 engine and 5-speed manual transmission. For those reading this in the future, you would regret regearing to only 4.56 for that combination.

My 4.88's work great for me on 35's but I get some added benefits from having the Rubicon TC
 
I am really in no rush. I really don't have an excuse when there are SO many videos and guides detailing it. I think, for me, it's less about saving money and more about learning about my rig in particular. I am an engineer by trade so this is really just fun and interesting for me. Not a daunting task that needs to get done.

Feel free to screenshot this post LOL it might age really well

It sounds like you have the right attitude about learning! I appreciate learning something for learning's sake. Go for it, I say! It won't be easy, but that's not the point!
 
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