4.88 or 5.13 gears?

Calvin.8

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Iola KS
So next up on my upgrade list (after some frame/rust repair first) is regearing and adding lockers. I currently have 33s on 3.73 gears and it is my DD, and not sure whether to go to 4.88 or 5.13s. The reason I have 5.13s on my mind is because I do want to eventually move to 35s. However, this will be quite a ways down the road so that I have time to upgrade parts to accommodate the 35s, which at that point it will not be my DD anymore. So I guess my question is how are the on-road characteristics of 33s with 5.13 gears, and does 35s with 4.88 feel painfully slow.

I have the 4.0L with the 5 speed manual transmission btw.
 
it's expensive to run 35's...is the rest of your Jeep up to it?

can't help with gear selection, since my TJ Sport is a stock auto on 33's, and my YJ runs 4.88's on 31's, but it's a 4 cyl.
No it's not up to it right now. But I'm still going to be running 33s for awhile and just slowly make upgrades to it until it is finally ready. I just don't want to have to regear again once I do end up making the switch to 35s.
 
5.13 would definitely be better for 35's. 4.88 would probably be better for 33's though.

I used to have the 6 speed and 35's with 5.13. It was good, but even lower would have been better. Just can't go lower with oem diffs.

Though having the 5 speed does compensate for not having the gears perfect. You could really go either way and it wouldn't be that bad. My Jeep originally had 4.56 with the 6 speed and 35's. It wasn't bad. Just eventually broke something so it was time to regear.

So I don't think 4.88 would be bad with 35's. Just better for 33's. Really up to you. 4.88 is going to be better for DD and gas mileage. 5.13 would be better for wheeling.
 
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No it's not up to it right now. But I'm still going to be running 33s for awhile and just slowly make upgrades to it until it is finally ready. I just don't want to have to regear again once I do end up making the switch to 35s.
@jjvw ran 4.88/33s/5 speed and I recall him posting that he'd rather have had 5.13s. He does live in Colorado, though. If you want to move to 35s, 5.13s are the way to go. Running them with 33s will motivate you to save up for everything 35s-related. ;)
 
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@jjvw ran 4.88/33s/5 speed and I recall him posting that he'd rather have had 5.13s. He does live in Colorado, though. If you want to move to 35s, 5.13s are the way to go. Running them with 33s will motivate you to save up for everything 35s-related. ;)
Even around town where is it as flat as Nebraska, I would prefer the lower gears.
 
5.13 gears it is then. And just making sure, when getting an Eaton E-Locker or ARB locker, they replace the carriers and new carriers are not required?
 
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5.13 gears it is then. And just making sure, when getting an Eaton E-Locker or ARB locker, they replace the carriers and new carriers are not required?
The entire thing gets replaced.
 
I have a 6 speed so not sure how much different the 5 speed would make. I am running 4:88's on 35's and mine drives like it did with the stock tires. Also mine is a Rubicon so off road I have lower gears in the TC so that may makes a little difference.
 
I have a 6 speed so not sure how much different the 5 speed would make. I am running 4:88's on 35's and mine drives like it did with the stock tires. Also mine is a Rubicon so off road I have lower gears in the TC so that may makes a little difference.
I have a feeling the transfer case would help slightly but not entirely sure if it would be noticeable. I just see tons of people that have tires that are "too big" for their gearing. Haven't found anyone talking about what driving a jeep with lower gears for your tire size would do.
 
I have 5.13 w/35's. Love it! I can daily drive it but my commute is only 6 miles. It'll do highway speeds just not getting anywhere fast
 
Haven't found anyone talking about what driving a jeep with lower gears for your tire size would do.

How bout 5.13 gears and 31" tyres? With my 5 speed I would not use 1st gear on the street. Sure was quick off the line though it cost me cruising speed on the freeway. I was set up for 35's before I bought 35's.
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5.13s work great but the tooth contact on the ring gear from the pinion gear is less putting more pressure on just 1 tooth. I know plenty of people with 5.13s and have had no issues.
 
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5.13s work great but the tooth contact on the ring gear from the pinion gear is less putting more pressure on just 1 tooth. I know plenty of people with 5.13s and have had no issues.
Though there is also a mechanical advantage from the lower gear ratio that decreases the force to turn the gears offsetting the smaller contact area.
 
Though there is also a mechanical advantage from the lower gear ratio that decreases the force to turn the gears offsetting the smaller contact area.
With a Dana 44 front or rear, the ring gear is larger allowing more tooth contact.
 
5.13s work great but the tooth contact on the ring gear from the pinion gear is less putting more pressure on just 1 tooth. I know plenty of people with 5.13s and have had no issues.

The shop that did my regear suggested 4.88 gears for more strength than the 5.13.

What was your max speed with that setup?

Kept it at 65mph at 3k rpm's.
 
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I'm in hilly western PA - 32s with 4.88s and 42RLE. I'm churning a little higher than I'd like on the highway but it definitely handles the hills a lot better. I would say a lot depends on future tires, terrain, and type of driving. I wanted a little breathing room to step up to 33s so I went 4.88s but have no desire to go any bigger.
 
I am a fan for going deep as you can. My 5.13s/35s have been great especially going over our mountain passes, I can hold 60 mph pretty well going up a 7-10% grade.
 
How bout 5.13 gears and 31" tyres? With my 5 speed I would not use 1st gear on the street. Sure was quick off the line though it cost me cruising speed on the freeway. I was set up for 35's before I bought 35's.
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But just think RINC, you could have had a CJ-2A with 5.38 axles , 6.00 - 16 tires with a 28.3 dia. and no overdrive ! All being pushed by a 60 Gross hp.
flathead 134 cid 4 banger.

By comparison your TJ is a freaking Bonneville landspeed record setting streamliner ! :LOL:
 
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