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3,o7 to 3.55 gearing

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Old 03-19-2014, 11:35 PM
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Default 3,o7 to 3.55 gearing

so im finaly putting lift in the front and was going to just replace all the steering components and the axle since its got a deathwobble and the bearings are going out. but i looked and my axle is 3.07 and the other is 3.55. i use 4x4 daily so i cant just put the front on. my back axle is welded and i would like to keep it that way so could i just swap the spiders from mine to the 3.55 axle on the rear. is it a lot better to have 3.55. mines realy slow starting out with the 3.07.
Old 03-20-2014, 01:13 AM
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3.55 is way better for the manuals with bigger tires. My cousin had 3.07 with 33s and it lacked power big time. 5th was useless other than on flat road.
Old 03-20-2014, 02:28 AM
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Tire size?
Old 03-20-2014, 05:32 AM
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3.55 gears in a manual trans is the equivalent of us autos gearing to 4.10s. What size tires are you going to and ill crank out the math for you.
Old 03-20-2014, 05:35 AM
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Originally Posted by Outlaw Star
3.55 gears in a manual trans is the equivalent of us autos gearing to 4.10s. What size tires are you going to and ill crank out the math for you.
Be careful dont bust a vein this early ...lol...
Old 03-20-2014, 05:42 AM
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I'm confused. Is your truck a factory manual or automatic? You said one axle is 3.07 and one is 3.55 but which one? I can only assume since you noticed 3.07s when you were inspecting the front end, your front is geared as such. If that's the case, then someone swapped out the axle due to an accident and didn't know what they were doing. Your front and rear axle gearing need to be damn near matching for 4WD to work properly.

How are you using 4wd with mismatched gears? Regardless, it's easier to find a Dana 30 or Chrysler 8.25 with 3.55 gears and just swap it over than to replace all the spider gearing. Do that.
Old 03-20-2014, 05:54 AM
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Originally Posted by Battle
I'm confused. Is your truck a factory manual or automatic? You said one axle is 3.07 and one is 3.55 but which one? I can only assume since you noticed 3.07s when you were inspecting the front end, your front is geared as such. If that's the case, then someone swapped out the axle due to an accident and didn't know what they were doing. Your front and rear axle gearing need to be damn near matching for 4WD to work properly.

How are you using 4wd with mismatched gears? Regardless, it's easier to find a Dana 30 or Chrysler 8.25 with 3.55 gears and just swap it over than to replace all the spider gearing. Do that.
2 different Jeeps ...
Old 03-20-2014, 06:57 AM
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A 4.0L with 3.55:1 behind a stick is good to about 32s. More than that and you'll want to gear deeper again.

I believe the spiders have to come out in order for the side gears to move. So no, I don't think you can just swap the guts of the diff over to a new axle.

If you're going through all this trouble just get a lunchbox locker.
Old 03-20-2014, 09:50 AM
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I've been running 33s ever since I got the jeep and I always hated the gearing. Never used 5th gear. It manual. So i can't just swapp the spiders. So should I just run open open till I find a locker or have time to weld it.ps I have to drive threw fields on the way to school and almost got stuck yesterday 4low reverse for 5mnts thank god got me out
Old 03-20-2014, 10:38 AM
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thanks for the info guys so my rig sees alot of raod also and its been eating my tires. so should i go wth a limited slip locker.would i see a big difference between it and a welded rear end
Old 03-20-2014, 10:41 AM
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Originally Posted by 88mudfinder
thanks for the info guys so my rig sees alot of raod also and its been eating my tires. so should i go wth a limited slip locker.would i see a big difference between it and a welded rear end
Yes. The Powertrax No Slip is a good choice for on and off road usage and drops right in without messing with the ring and pinion. A fully welded or locked rear will eat your tires.
Old 03-20-2014, 07:56 PM
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Originally Posted by 88mudfinder
thanks for the info guys so my rig sees alot of raod also and its been eating my tires. so should i go wth a limited slip locker.would i see a big difference between it and a welded rear end

88mud, a limited slip differential, and a locker are two completely different things.

A limited slip uses clutches or torque biasing gears to transfer some power to the tire with the most traction. Unless the clutches are wore out then they work just like an open differential.

A locker uses gears to transfer 50% of torque to each tire anytime you are driving in a straight line or when you're gassing it.
If I were looking for better traction and tire wear I would be going with a Lunchbox locker, cheaper than a LSD and better traction.
Old 03-20-2014, 08:09 PM
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Originally Posted by Rock Toy
88mud, a limited slip differential, and a locker are two completely different things.

A limited slip uses clutches or torque biasing gears to transfer some power to the tire with the most traction. Unless the clutches are wore out then they work just like an open differential.

A locker uses gears to transfer 50% of torque to each tire anytime you are driving in a straight line or when you're gassing it.
If I were looking for better traction and tire wear I would be going with a Lunchbox locker, cheaper than a LSD and better traction.
Okay thanks but I'm just going to weld it. Looked at the prices and Don't have the money for a locker.
Old 03-20-2014, 09:07 PM
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Originally Posted by 88mudfinder

Okay thanks but I'm just going to weld it. Looked at the prices and Don't have the money for a locker.
DONT WELD for street usage. Stuff WILL break. Just stay open diff untill you can afford the right gear.
Old 03-20-2014, 09:57 PM
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Originally Posted by 88mudfinder
Don't have the money for a locker.
But you have money for tires?


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