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Differential Fluid change

wheels082

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I did mine at about 8,000 miles. The front was not too bad but the rear definitely needed it. After seeing how bad it was I think 5K would be good for a first change. I used the Severe Gear. It comes in a squeeze bottle making it super easy to fill the diffs back up.
https://www.amsoil.com/p/severe-gear-75w-90-svg/?zo=226468
 

Kluk Ztopolovky

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I understand that some owners believe the service manual is pretty much useless.
 

txj2go

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Drive around our freeways and count the number of Jeeps- it is doubtful if more than 2% every have any fluids changed other than motor oil. I was in an inspection/oil change place one time and overheard a guy telling a customer that she absolutely had to change her (automatic) transmission fluid every 24,000 miles. I don't think the service manuals are overly conservative so change it more frequently if you wish, but most of the time I don't think it makes much difference. Working in a garage you almost never see any problems with differential gears on cars and trucks with a whole lot of miles. And yes gear oil, at least dino oil, is horrible smelling stuff after it's been used a little bit.
 

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wv18jl

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Did mine @ 6.

It needed it.
 

tonygiotta

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Just did mine yesterday at 15K miles on my Rubicon with Amsoil Severe Gear 75W-110. Front looked great, rear wasn't horrible. Both magnetic drain plugs had a nice smooth paste of metal particles stuck to them, but nothing alarming. Did mine mostly for peace of mind that the gears were breaking in properly, but also because a deep water crossing, 200 miles of desert off-roading, and 15K on the odometer all aligned upon my return from the Mojave Road. Easy job with those drain plugs on there, I've always had to crack the covers in the past. (I did check torque on the cover bolts for good measure though.)
 

Kraty1

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Changed my differential gear oil today, 11k miles, rear was jet black but front wasn’t bad at all, no metal on the drain plug magnets but a tiny bit of of grey sludge was there. Overall very easy to do, used Royal Purple 75w-140 in the rear and then finished the bottle in the front before topping off with 75w-90. After adding the friction modifier in the rear I used less than 3 1qt bottles total.

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PatrickR

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I changed mine at 10k as well (LSD), It was dark with grey sludge on the mag plug, but I also didn't have any metal. I wish I had done it a little sooner. It takes all of 10 minutes (if you're taking your time) and $25 for the oil....
 

SecondTJ

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Overall very easy to do, used Royal Purple 75w-140 in the rear and then finished the bottle in the front before topping off with 75w-90. After adding the friction modifier in the rear I used less than 3 1qt bottles total.
I thought all Royal Purple already had fiction modifier in it?

You don’t want to double up on it because it allows too much clutch slippage. It helps longevity but renders the LSD less effective.
 

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PatrickR

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I thought all Royal Purple already had fiction modifier in it?

You don’t want to double up on it because it allows too much clutch slippage. It helps longevity but renders the LSD less effective.
I'm with you on that one. I used an oil with the additive already in it, and added none. No issues and it seems like the clutches engage a little better than before.
 

madscientist

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I thought all Royal Purple already had fiction modifier in it?

You don’t want to double up on it because it allows too much clutch slippage. It helps longevity but renders the LSD less effective.
This was my thought also... that's why I want to use the RP when I change my fluid.
 

dugal

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I have over 20K on my JLU Sahara. After my last Wave free oil change, the dealer recommended changing the diff fluid. Got ready to change it and saw the square end on the bolts and didn't know what tool to use? Need assistance. Thanks
 

wheels082

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I have over 20K on my JLU Sahara. After my last Wave free oil change, the dealer recommended changing the diff fluid. Got ready to change it and saw the square end on the bolts and didn't know what tool to use? Need assistance. Thanks
It is a standard 3/8 square. Use a 3/8 drive ratchet.
 

dugal

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