Re-gearing questions

I'm going to stay with the 4.56, my JKU is my daily driver. I don't do a lot of off road and when I do it's usually to too difficult. I just want it back in the factory power band.
 
Would 4.88 be too much for 33 or 34" tires? Currently on km3s and stock 4.10 but might switch.
 
I think it will depend on how much and what kind of wheeling you do. If its your daily driver then you will be running high RPM's with 33's. If you have 4.10's now I wouldn't bother. But again it depends if it's your daily driver and how hard your wheeling is.
 
The time has come! The jeep goes in the shop tomorrow to remove the 3.21's and get her new 4.56's. Also going from open differentials to limited slip differentials.
I just want to be sure about the Jscan, I purchased the license so I can tell the jeep the new gear size. Is that all I need to do?
 
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Yes. I went on YouTube and found out that there is about a total of 3 steps that need to be done in jscan after the gears have been changed.

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I would expect the shop to do that sort of thing. I'm sure you are paying them enough.

That being said, Jscan is an amazing app for Jeepers, and a must have for anybody who's jeep isn't stock.
 
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The shop I took it to is Connecticut Axle & Spindle. They do more of commercial vehicles. They do jeeps but it's not their main business. He was well aware of the need for the jscan.
 
Axle update. Everything went perfectly with the gear replacement. I got rid of the 3.21 gears with an open differential and installed 4.56 gears with limited slip differentials. The jscan worked awesome. Three simple steps and I was off to the races. Now I just have to do the break-in for 100 miles the change the gear oil in 500 miles. I was very impressed with the shop that did it. He started on it this morning and by 2:30 it was done. It's pulling the hills better and it not down shifting less on the hills. Very pleased with the outcome.

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nice!

If you are willing to tell us, what was the cost? Also drop the name of the shop since you are pleased. This gives a baseline for others looking to do this sort of thing.
 
Sure the out the door price was $3200. The shop was CT Axle & Spindle in Ellington Connecticut. All the gears came from RGD Technologies in Bristol Connecticut.
 
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It would have been only $2k if I just replaced the gears and kept the open differential but I wanted to upgrade a bit. I don't do enough off-road wheeling to justify the additional cost for lockers. So I just went with the Limited slip differentials. Those are made by Yukon.
 
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@SteveF I'm all for throwing money at smaller businesses when I can, even if it's a few bucks more. I went to the RGD Technologies and CT Axle & Spindle websites. I couldn't find anything about r&p's at the RGD site and the CT site only mentions Yukon and Revolution parts. Do you have any additional info on the RGD gears?
 
Hmm. Was considering the Detroit Truetrac - wasn't aware Yukon had a helical LSD. Does it pull to one side until the oil has warmed up or haven't you had a chance to get a feel for it yet? My installer doesn't recommend LSD's in front for snow/ice, and he repeats all the tropes on the internet about why you shouldn't do it, but I need to ask how many he's installed. Every posting from someone who HAS a Detroit Truetrac in front and drives in snow and ice has reported positively. Others who warn of the Collapse of the Known Universe if a TT is installed in front don't own one.

I have hesitated because 1) I only want to do this once and 2) my wife will occasionally drive it. But to be honest, #2 isn't much of an issue because she doesn't like driving the JK in the snow - for a long time she would never ask me how to engage 4wd (smh).
 
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