Educate me on axles

inkedrose

inkedrose

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Looking to upgrade rear axel shafts. 2004 Rubi, geared to 5.13, stock F&R lockers, on 35's. If I've read correctly, splines need to match lockers and spider gears? Stock rubicon is 30 spline, so if I have stock lockers is it safe to assume the shafts that are in are currently 30 spline? I'm 2nd owner, PO did a lot of work but shaft upgrades weren't mentioned. Are there any other wearable parts I should be changing while I'm in there? Watched HorseJockys video, seems like a straight forward project? Says "smaller parts must be purchased separately", what else do I need? Revolution keeps coming up as the recommendation & comes with bearings already pressed. Anything else I need to know?

https://www.revolutiongear.com/prod..._brake_4140_chrom_moly_rear_axle_kit_87_06_tj
 
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tworley said:
30-spline locker requires 30 spline shafts. So yes, your stock lockers are 30 spline. The rear 44 on a rubicon does not use spider gears. So new shafts are plug and play. The RG&A are already assembled minus the wheel studs.
Click to expand...

awesome thanks man. That seemed to easy, wanted to double check. Any guess why front has them and rear doesn't? I guess I don't understand the purpose of them. From what I read they take pressure off to help one wheel spin faster or slower through a turn. That seems like it would be needed on both ends?
 
inkedrose said:
Looking to upgrade rear axel shafts. 2004 Rubi, geared to 5.13, stock F&R lockers, on 35's. If I've read correctly, splines need to match lockers and spider gears? Stock rubicon is 30 spline, so if I have stock lockers is it safe to assume the shafts that are in are currently 30 spline? I'm 2nd owner, PO did a lot of work but shaft upgrades weren't mentioned. Are there any other wearable parts I should be changing while I'm in there? Watched HorseJockys video, seems like a straight forward project? Says "smaller parts must be purchased separately", what else do I need? Revolution keeps coming up as the recommendation & comes with bearings already pressed. Anything else I need to know?

https://www.revolutiongear.com/prod..._brake_4140_chrom_moly_rear_axle_kit_87_06_tj
Click to expand...
Just make sure to select the right model rear axle shafts to match your rear brakes, drum or disk. The axle retainer brackets are slightly different for drum vs. disk. :)
 
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inkedrose said:
awesome thanks man. That seemed to easy, wanted to double check. Any guess why front has them and rear doesn't? I guess I don't understand the purpose of them. From what I read they take pressure off to help one wheel spin faster or slower through a turn. That seems like it would be needed on both ends?
Click to expand...

Selectable lockers function as an open differential when off. Essentially, the spider gears are internal to the locker assembly. This applies to front and rear axles on the Rubicon.
 
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inkedrose said:
awesome thanks man. That seemed to easy, wanted to double check. Any guess why front has them and rear doesn't? I guess I don't understand the purpose of them. From what I read they take pressure off to help one wheel spin faster or slower through a turn. That seems like it would be needed on both ends?
Click to expand...

The rear locker is a limited slip with helical gears inside. Not sure why they were only used in the rear. They can still be damaged, but as far as I am aware there is no way to replace them. My old rubi locker I suspect had the helical gears damaged. I accidentally hit the locker button when shifting into 3rd gear. Shortly afterwards I was getting a really bad bind/pop when turning. There were small bits in the gear oil, but I couldn't find exactly where they came from.
 
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Marklar1983 said:
Selectable lockers function as an open differential when off. Essentially, the spider gears are internal to the locker assembly. This applies to front and rear axles on the Rubicon.
Click to expand...

That makes sense. thank you for the explanation
 
super easy swap. Just make sure you order it for drums or discs as appropriate so you get the right backing plates. I'm pretty sure I had mine swapped in under an hour. Raise and change one side at a time so the gear oil flows toward the low side and you won't lose any out the end.
 
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It sounds like you already made the order,but the stock locker is your weak link in the rear. Saving for an arb or elocker would happen first if i was to do it again knowing that
 
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Rickyd said:
It sounds like you already made the order,but the stock locker is your weak link in the rear. Saving for an arb or elocker would happen first if i was to do it again knowing that
Click to expand...

That's on the "eventually" list too. Have an ARB compressor mounted already. Bought it with intention of going that route but I keep finding other shiny things
 
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O.P. has a Rubicon which all come factory equipped with discs. @inkedrose , not mentioned is that the Rubicon rear axle uses different shaft lengths between left and right.
 
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sierradmax said:
O.P. has a Rubicon which all come factory equipped with discs. @inkedrose , not mentioned is that the Rubicon rear axle uses different shaft lengths between left and right.
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The Dana 44 uses different length shafts for each side. This isn't specific to the Rubicon. The long and the short lengths of the rear match the orientation of the front axle.
 
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tworley said:
The rear locker is a limited slip with helical gears inside. Not sure why they were only used in the rear. They can still be damaged, but as far as I am aware there is no way to replace them. My old rubi locker I suspect had the helical gears damaged. I accidentally hit the locker button when shifting into 3rd gear. Shortly afterwards I was getting a really bad bind/pop when turning. There were small bits in the gear oil, but I couldn't find exactly where they came from.
Click to expand...

Your locker broke apart from a shock load while it was engaging at speed. The locker bits may have then clogged the helical gears in the LSD.

The Rubicon lockers are not serviceable or repairable. Break one and it needs to be replaced.
 
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