# Why is my rear pinion seal leaking?



## jimchevy (Dec 29, 2011)

I just had a new pinion seal installed 2 weeks ago and it still leaks pretty bad. Assuming the new seal was not nicked in any way and installed properly, what other reasons would cause it to still leak?? Any ideas would be appreciated.


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## BearGFR (Aug 25, 2008)

If there's really nothing wrong with the seal (and it was installed correctly etc.etc.), and if it's definitely leaking around the seal and not from somewhere else (like a cracked housing), then perhaps the problem is a groove or some other "void" around the circumference of the shaft providing a leakage path past the seal.

Bear


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## geeteeohguy (Feb 2, 2008)

Generally, new seals leak when the cause of the failure of the first seal remains. Usually, it's a worn bushing, bearing, or groove in a shaft. I had the same problem with the gearbox in my '65 about 20 years ago....replaced the tail shaft seal, only to have it leak again shortly after. Cause? the bushing was worn out and the drive shaft yoke was worn out, as well. My bet is that your rear flange is worn or walking around a bit due to a worn bearing. Take it back to the shop that did the work and let them now that their repair was unsuccessful.


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## jimchevy (Dec 29, 2011)

Thanks for the info guys. I was thinking along the same lines. I took it to a friend of a friend who owns a shop that specializes in transmissions. He was up front with me and said he doesn't do many rears anymore. He didn't charge me to change the seal. The previous owner rebuilt the rear less than two years ago and may not have set it up properly. Today, I called another buddy of mine who is a mechanic and he wants me to bring the car in next week with a new seal just in case the seal was done properly a few weeks ago. I might pick up a redi-sleeve: Buy National Redi-Sleeve 99193 at Advance Auto Parts also in case we find a groove in the yoke although I never used one. I'll report back with results next week! Hopefully my housing has no cracks.


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