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Easy way to check inner axle seals?

wolf1790

New Member
Apr 27, 2019
13
Florida
Installed new ball joints and when I removed my axles, there was quite a bit of differential fluid that leaked out of the axle tubes. Afterwards, I've had a slow leak from the tubes, but only after a drive.

My jeep also has those dumb outer axle seals. My theory [hope] is that those outer seals are holding the fluid in the tubes except when I'm driving, and that maybe my inner seals are fine.

Is there a way to easily test the inner seals to verify if they're leaking or not?
 

Rob5589

Certified video trained differential rebuilder
Supporting Member
Aug 29, 2016
6,210
W Sacramento, Kalifornia
The way to check if they are leaking, is seeing fluid leaking out of the axle tube. Those outer seals aren't helping or keeping the fluid in the differential where it belongs. It would take a significant amount of oil to fill the center section and tubes to keep everything lubricated properly. You need to replace them if you are seeing fluid leaking.
 
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OP
wolf1790

wolf1790

New Member
Apr 27, 2019
13
Florida
I think you both misunderstood my question. I'm aware that the diff has fluid and not the tubes. I'm saying that when I removed the axles to replace my ball joints, fluid was displaced from the differential into my tubes. What's a good way to determine if it's just the residual fluid from when I removed the axle, or a leaking seal.
 

Rob5589

Certified video trained differential rebuilder
Supporting Member
Aug 29, 2016
6,210
W Sacramento, Kalifornia
Hose out the tube and see what happens. There is no way to check the seal. The chance that you caused the seals to leak on a 20 year old rig are close to 100%.