Yup. I have one the axle seals failed in.. I replaced the seals [Rear end axle seals 90310-5006] on 8/20/2016 98 Sr5 Red [Tetanus1] with my odometer 218289.
I just changed the seals only.. Still not leaking at 9/4/2019 with 255029.
So yes at some point, your axle bearings are going to get you if not replaced.. As they haven't got me yet... { i changed the breather as well }.I am planning on changing my rear end and front end on that rig at some point as my housing in the rear is jb weld sealed from leaking at the moment. The previous owner let it go low a few times so my rear end has seen better days ( it actually has locus heavy duty oil stabilizer at 100% in place of gear grease... has since 2016.. A little noisy at 70mph below 60mph purrs quiet as a church mouse....LOL. I am sure the locus has nothing to do with not leaking too..
The Folks are correct though.. The grease is gone in those axle bearings... The correct way to fix it is to replace them. ;-)
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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