What gears do I want?

I took all your advice and placed an order for 5.13 gear install kit. I reached out to East Coast Gear Supplies and got the recommended Yukon parts.
Dana 30 ring and short pinion in 5.13 along with the master install kit
Dana 30 3.73 and up carrier
Dana 44 ring and pinion in 5.13 thick cut gears along with master install kit
Parts will take several weeks to reach me and I will report back with how I like them once installed.
Thanks again for the detailed instructions from everyone.
 
After months of waiting on freight and waiting for an appointment at the dealer, I finally got the installation done this week. The drivability of the jeep has improved significantly and it gets to the power band more easily. Also, I didn't notice over-revving at speed at higher gears either. Obviously I haven't pounced on the jeep until the gears are broken in so I haven't tried hard launches or anything to see the full effects but overall I'm happy I went with the 5.13s even with the 33s I have now.
 
After months of waiting on freight and waiting for an appointment at the dealer, I finally got the installation done this week. The drivability of the jeep has improved significantly and it gets to the power band more easily. Also, I didn't notice over-revving at speed at higher gears either. Obviously I haven't pounced on the jeep until the gears are broken in so I haven't tried hard launches or anything to see the full effects but overall I'm happy I went with the 5.13s even with the 33s I have now.
Correcting the axle gear ratio is some of the best money we can spend on our rigs. I remember one of my first reactions after installing the new gears: Why didn't I do this sooner?!
 
Correcting the axle gear ratio is some of the best money we can spend on our rigs. I remember one of my first reactions after installing the new gears: Why didn't I do this sooner?!
True, Reminded me how my previous JK2D felt. As if the Jeep forgot it had oversized tyres :)
 
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After months of waiting on freight and waiting for an appointment at the dealer, I finally got the installation done this week. The drivability of the jeep has improved significantly and it gets to the power band more easily. Also, I didn't notice over-revving at speed at higher gears either. Obviously I haven't pounced on the jeep until the gears are broken in so I haven't tried hard launches or anything to see the full effects but overall I'm happy I went with the 5.13s even with the 33s I have now.

Diggin up old thread... Sorry
So after having the 5.13 gears awhile what's your opinion of the performance now?
Did you ever get the driveline vibes some have had with going to 5.13 gears because of driveshaft rpm's?
I'm about to make a decision on which gear ratio I will go with (also considering 4.88). My Jeep is a 2006 LJ Rubicon with the dreaded 42rle Auto Tranny, 33 inch tires. Illinois is pretty flat.
 
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Did you ever get the driveline vibes some have had with going to 5.13 gears because of driveshaft rpm's?
If they did get vibes there is no way to balance the driveshaft. There are no machines available capable of balancing at that speed. If you get the gears plan on either re-gearing again or spending well in excess of that to get locking hubs. Nothing wrong with getting whatever gears you want but be prepared for the outcome. Planning on not having problems is poor planning. Just because one or two didn't have vibes doesn't mean you wont, it's just a roll of the dice no matter how many times you ask.
 
If they did get vibes there is no way to balance the driveshaft. There are no machines available capable of balancing at that speed. If you get the gears plan on either re-gearing again or spending well in excess of that to get locking hubs. Nothing wrong with getting whatever gears you want but be prepared for the outcome. Planning on not having problems is poor planning. Just because one or two didn't have vibes doesn't mean you wont, it's just a roll of the dice no matter how many times you ask.

This is exactly why I'm leaning hard towards 4.88 gears. I dont want to be spending money for a long time chasing vibes down. My Jeep has only 40k miles on it now, Im hoping I will be one of the lucky ones that get by without driveline vibes. I have read and read threads and I just cannot talk myself into 5.13 gears. If I decide on 4.88 I hope I will never regret it.
 
Diggin up old thread... Sorry
So after having the 5.13 gears awhile what's your opinion of the performance now?
Did you ever get the driveline vibes some have had with going to 5.13 gears because of driveshaft rpm's?
I'm about to make a decision on which gear ratio I will go with (also considering 4.88). My Jeep is a 2006 LJ Rubicon with the dreaded 42rle Auto Tranny, 33 inch tires. Illinois is pretty flat.

Most vibe issues are solvable with enough time and money (manual hubs and pinion adjustments). I'd go deeper than you'd expect with the 42rle. I'm on 35s with 5.13 and just swapped the NSG370 (where the gearing was just right) to the 42RLE (where I wish I had 5.38). Granted I have mountains to deal with.
 
This is exactly why I'm leaning hard towards 4.88 gears. I dont want to be spending money for a long time chasing vibes down. My Jeep has only 40k miles on it now, Im hoping I will be one of the lucky ones that get by without driveline vibes. I have read and read threads and I just cannot talk myself into 5.13 gears. If I decide on 4.88 I hope I will never regret it.
You'd definitely regret 4.56. I'd decide strictly between 4.88 and 5.13. Personally I'd go 5.13.
 
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This is exactly why I'm leaning hard towards 4.88 gears. I dont want to be spending money for a long time chasing vibes down. My Jeep has only 40k miles on it now, Im hoping I will be one of the lucky ones that get by without driveline vibes. I have read and read threads and I just cannot talk myself into 5.13 gears. If I decide on 4.88 I hope I will never regret it.

Ask a few local gear shops that you are considering to do the install, nobody here is going to cover the work if there are vibes. No gear shop I've ever talked to would recommend these high ratios. Even Tom Woods says it's too fast for them to balance. No matter what decision you make you'll have second thoughts, that's part of life. These ultra high ratios aren't what they make them out to be, most people with those ratios don't daily drive their rigs anyway.
 
I'm probably going with 32" tires on JK Moab rims. May stick with the Canyon rims and go with 32.5" (33" nominal). Both in 10"-10.5" width. In any case won't be going larger in my lifetime. Have pretty much decided on 4.88 gears to make the drop down to 3rd not so drastic with the 42RLE transmission and keep the O/D revving a little lower on the freeway. Figure 4.88 gears won't have the O/D dropping In and out with the slightest incline like it does with the stock 29.5" tires and 3.73 gearing and still give good off the line performance. 5.13 gears are tempting but afraid the freeway rev's will make the already poor gas mileage worse. Took advantage of the Amazon good deal on the Yukon 07 locking hubs so not concerned with front driveshaft vibration. Like to hear others experience with 32"-33" tires running 4.88 gears.
 
Ask a few local gear shops that you are considering to do the install, nobody here is going to cover the work if there are vibes. No gear shop I've ever talked to would recommend these high ratios. Even Tom Woods says it's too fast for them to balance. No matter what decision you make you'll have second thoughts, that's part of life. These ultra high ratios aren't what they make them out to be, most people with those ratios don't daily drive their rigs anyway.

Yea I already have been talking to a couple gear shops. They both say to go with 4.88. My Jeep is not a daily but I do drive it alot and mostly highway miles.
 
I've never heard this. Is this true @Shawn at Tom Wood's ? Funny thing is I regeared to make the street driving better. Off road didn't care quite so much, though it was noticeable.

Shawn wrote this earlier ..

https://wranglertjforum.com/threads/drive-shaft-vibrations.63323/post-1146345
I regeared for the same reason with 4.88s and 32s the 1st time when I got the demon vibes. When I went to 33s, I drove with 4.88s for a while before I decided I wanted 5.38s, it was that miserable. I don't know what is more painful to live with, demon vibes or an undergeared jeep that you drive on the hwy. Most people would choose the former if asked that question I guess .. but it SUCKS driving an improperly geared Jeep if you live in a hilly area. I simply don't understand how people do 3.73s and 33s or whatever.
 
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Shawn wrote this earlier ..

[URL]https://wranglertjforum.com/threads/drive-shaft-vibrations.63323/post-1146345[/URL]

I regeared for the same reason with 4.88s and 32s the 1st time when I got the demon vibes. When I went to 33s, I drove with 4.88s for a while before I decided I wanted 5.38s, it was that miserable. I don't know what is more painful to live with, demon vibes or an undergeared jeep that you drive on the hwy. Most people would choose the former if asked that question I guess .. but it SUCKS driving an improperly geared Jeep if you live in a hilly area. I simply don't understand how people do 3.73s and 33s or whatever.

Thank you! I remember reading that now that I've read it again. And I'd happily make the tradeoff of servicing my drive shafts more regularly. I just burned through my first centering ball in 2.5 years - easy trade off.
 
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Realize that there is no magic line between 4.88 and 5.13 where vibes appear. Some get them with 4.56 and some don’t get them at all with 5.38. Obviously the deeper you go the faster the shaft is spinning and more chance for vibes. Both 4.88 and 5.13 are deep enough that you’re in vibe risk territory. Personally I’d choose what makes the Jeep drive the best over delaying vibes a few mph.