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Hi everyone, so I just replaced my totaled wrangler with a new(to me) tj. It’s a 5 speed manual 4L in-line 6. As it sits, it’s got stock axles, Dana 35 rear, 30 front I believe, and it has a 4 in lift running 35’s. Around town and up to 45mph it runs pretty good for stock gears and 35’s. But on the highway 4th is a must for most of it and even at 65-75 I only reach about 23-2400rpms in 4th. So I know re-gearing is in my near future as this is my daily and I do occasionally take trips involving some decent miles on the highway.

So I’ve read a bunch of threads and have heard a number of different options, either 4.10’s, 4.56, 4.88, some people even suggesting 5.38’s. So for someone who does daily 10mi on the highway and daily driver/weekend toy, what would be the best option? Also, will I have to do axle swaps to gear with certain ratios? I’d like to avoid that. (Obviously will be doing this through a shop not myself lol). Any help would be appreciated in the matter!
 

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You are likely to get a wide variety of opinions just as your search revealed. My suggestion would be to do all axle improvements at the same time. Do the re-Gear, improved axles, lockers and whatever all at the same time. I am running 4.56, truetrac, 35s and 4140 axles and never had any problems or complaints. Of my fleet of trucks cars and bikes my Jeep is my go to vehicle. I use it around town, highway and a lot of desert exploring.
 

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I am not an expert on that transmission. I have a 42RLE 4 speed automatic.

I also have a HP30 front axle and a D44 in the rear. Running 33" MT/Rs. A year ago I had the axles regeared to 5.13. This was the lowest ratio available for the HP30. It looks like that is still true today.

https://www.revolutiongear.com/prod...jeepdanaamc_ring_pinion_sets/category/dana_30

Using grim reapers Gear ratio calculator :

Gear Ratio Calculator

5.13s would put you at the same rpms in road gear with 35s as me at 70 mph.

I am sure others with more experience with your transmission will be in here before long but in the meantime that calculator might give you something to ponder!
 

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It's not opinions as much as fact. 4.88 is optimal for a 5 speed, 35s and 4.0L engine. I chose 5.13 because it works a little better for me.
 
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I am not an expert on that transmission. I have a 42RLE 4 speed automatic.
Did you follow me from that other forum? :beerdrinking:
 

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So my post is a little different. I’m running 31” tires, street driving great, no lift at thus time. If I did lift, I would only go 2/ 2 1/2, with maybe 33” tires. Dana 30 front Dana35 back, stock 3.07 gearing, I have the original window sticker. I’m looking to just add a limited slip to the rear. Weekend fun, nothing big, no crazy stuff, thoughts?
 

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So my post is a little different. I’m running 31” tires, street driving great, no lift at thus time. If I did lift, I would only go 2/ 2 1/2, with maybe 33” tires. Dana 30 front Dana35 back, stock 3.07 gearing, I have the original window sticker. I’m looking to just add a limited slip to the rear. Weekend fun, nothing big, no crazy stuff, thoughts?
find someone that is swapping out either 3.73 axles or 4.10 axles and swap them into your jeep. the 3.07 gears are too low for a TJ, even with stock tires
 

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So my post is a little different. I’m running 31” tires, street driving great, no lift at thus time. If I did lift, I would only go 2/ 2 1/2, with maybe 33” tires. Dana 30 front Dana35 back, stock 3.07 gearing, I have the original window sticker. I’m looking to just add a limited slip to the rear. Weekend fun, nothing big, no crazy stuff, thoughts?
I had a Jeep with 33s and 3.07s for a couple of months. If you can live with it, it's your Jeep. Some people drive 4 cylinder Jeeps with 33s and stock gears and have no problems. For your needs, axles from a 4 cylinder 5 speed with 4.10 gears would be the least expensive route (I bought some for $300 a set).) 03-06' auto 4 bangers had 4.56. If you need any type of locker, do the front or you'll have to upgrade the rear axle to a S35 or better.
p.s. A limited slip is useless for most people's needs. I've found that two fat girls riding in the back seat worked better than a rear LSD.
 

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Damn, I should have added I have the 4.0 inline 6.
Everyone knew that and all advice applies. The 4 cylinder references are for your axle gearing. 4.0L have 3.07 or 3.73, unless you have a Rubicon with 4.10. TJ 4 cylinder Jeeps came mostly with 4.10 and newer autos with 4.56. All 4 cylinder Jeeps have the weaker D35 rear axle.If you have a D44 rear axle, your gears are 3.73 in the USA.
 

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I don’t have 2 fat girls to sit in back and had a lot of tire spinning this weekend in some mud that I was not happy with. That’s why I’m asking about adding posi to my rear, but don’t want to go crazy (money)trying to add a Dana44.
 

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I don’t have 2 fat girls to sit in back and had a lot of tire spinning this weekend in some mud that I was not happy with. That’s why I’m asking about adding posi to my rear, but don’t want to go crazy (money)trying to add a Dana44.
id think you'd be better adding an auto locker to the front. they run ~$250 and are invisible while on-road in 2wd
 
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