From what a gathered. Over the years. The weak spot in these diffs is the ring and Pinon. I just pulled the 3rd member out of this rusted housing. As it was noisy.
The carrier and spider assembly at a visual Glace looked fine. [283k ] on it. The pinion gear looks really polished. My guess along with randybodady is the Pinon shaft bearings have play. The upper one doesn't seem to. Yet I can feel play in the Pinon and ring gear. Thus I think where my noise was coming from. I didn't pull the 3rd member into pieces to verify.
My guess is my Pinon and ring gear have wear from it.
What I did. 70k miles ago was switch to locus heavy duty oil stabilizer to help reduce the noise as my housing was leaking too.
In my case, I believe the PO ran it low in gear grease a few times.
In your case, I suspect the transfer case explosion may have jarred or damaged something in the member.
The carrier looks good?
To fix this, your probably need to replace your Pinon bearings and verify your gear mesh is good..
Sent from my SM-A505U using Tapatalk
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7 3rd gens listed in the build thread (2 are parts mobiles)
Build Thread:
https://www.toyota-4runner.org/3rd-g...os-builds.html
Brillo's Bucket Fluid Ex changer:
https://www.toyota-4runner.org/3rd-g...ml#post3358086
Sparks Plugs Wire and Coil Information:
https://www.toyota-4runner.org/3rd-g...on-5vz-fe.html