Transfer case, front axle, and rear diff fluid change.

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Soliyou

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Here is the message I received (while towing my boat with a spare tire installed)
In such situation, it is always better to use the spare tire on one of the front axle and move that front tire to the back in place of the flat. The differential, even non lsd, will overheat because of the difference in overall tire diameter. Even my Corolla’s front diff whined like crazy with the spare tire on the front axle!

I guess the message that you got was normal in your situation and shouldn’t trigger a fluid change.

That said, I did change my diff fluid early, I guess around 20k, and the fluid didn’t look good (looked like green paint mixed with silver paint). So I am glad I did it that early to get rid of break-in metals.
 
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Overtow

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I went thru with the fluid change - the old fluid was clear and did not smell 'burned', so I probably didn't need to change it. I can rest easy now though knowing that I have fresh synthetic gear lube in the rear end though.

The process of changing the fluid was easy - 3/8th ratchet and some thread locker is all that is needed. Dropping the spare out of the way made it easy to suspend the new gear oil jug above the fill point which made the fill relatively painless. The hardest part was not getting gear lube everywhere, which I managed to do, thus I didn't get any pictures...
 

duneslider

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I went thru with the fluid change - the old fluid was clear and did not smell 'burned', so I probably didn't need to change it. I can rest easy now though knowing that I have fresh synthetic gear lube in the rear end though.

The process of changing the fluid was easy - 3/8th ratchet and some thread locker is all that is needed. Dropping the spare out of the way made it easy to suspend the new gear oil jug above the fill point which made the fill relatively painless. The hardest part was not getting gear lube everywhere, which I managed to do, thus I didn't get any pictures...
I have horrible luck when doing diff fluid, some how I always manage to make a mess. One time I set the bottles down a few feet from the rear end and then decided to roll back a couple feet to make access to the front and back at the same time a bit easier, a bottle tipped over and rolled under the rear tire. You can imagine what happened next...
 

Soliyou

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I went thru with the fluid change - the old fluid was clear and did not smell 'burned', so I probably didn't need to change it. I can rest easy now though knowing that I have fresh synthetic gear lube in the rear end though.

The process of changing the fluid was easy - 3/8th ratchet and some thread locker is all that is needed. Dropping the spare out of the way made it easy to suspend the new gear oil jug above the fill point which made the fill relatively painless. The hardest part was not getting gear lube everywhere, which I managed to do, thus I didn't get any pictures...
Good that the fluid was clear, yeah, get those break-in metals out.

I hope you remembered to add the friction modifier.
 

ColoradoJon

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Hey, attempting to do this and I find the fill plug above the drain on the back plate of the differential. I thought it was forward near the driveshaft on the front portion from what I have researched. Just makes me nervous cause it seems lower, like only the bottom half of the gears are bathed in the oil. I suppose it spins and mixes it around while driving but wanted to confirm the placement? I have the 3L code axle with the lsd (HD tow).
 

LazSlate

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LOL these comments are always gold. Changing these fluids early is a 100% waste. But there will always be those who will.
Something like the rear diff is so robust it literally can run for 500k miles with zero Maintenace. Just cause you can do something and you claim its cheaper than the cost of new one is not reason to do it.
 

NickTheATC

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Sorry to hijack. Is there an easy way to tell which rear differential you have and if it has the limited slip?
 

JoJoDaClown

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Sorry to hijack. Is there an easy way to tell which rear differential you have and if it has the limited slip?
You need to look at the sticker on the axle to see what rear end you have. That will tell you if it's limited slip or not.
A note of caution, if you have limited slip, be careful changing your own fluid. The clutch packs are very picky and will fail if you put in too much friction modifier.
 
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