Transmission seal leaks - do I need to get this fixed?

[Walter Byrd]

I have a 1992 Festiva with a manual transmission.

The transmission seal was leaking. Mechanics are telling me that, to fix it, they would have to take the transmission apart. This is very expensive, and I am told, not really needed.

My brother-in-law put some anti-leak stuff in the transmission, and he checked it for a while, and said it was not longer leaking.

Do I need to fix this? Or can I just keep taking out the speedometer cable, and putting in new fluid, and anti-leak stuff?

[TominMO]

The mechanic is lying or incompetent. The seal is where the CV axle fits into the tranny. You drain the fluid, pull the axle, replace the seal, reinstall the axle, add fluid. About a one-hour job.

Sometimes the incorrect seal is used, even by professional mechanics, which causes leaking.

You could also try using thicker oil than auto tranny fluid, if that is what you are using. Because Advacnedynamix uses 20w50 racing motorcycle oil, that's what I use. Much thicker, less prone to leak.

[SiliconSoul]

I've also read here that some replacement C/V shafts can be machined past their limits causing leaks. Although I would imagine you would see that right away after installing a bad shaft.

[zoe60]

I have replaced the seal on my driver side about 4 times now. Used 2 springs in the last one. Tried a new, not rebuilt axle, and it still leaks! It's not horrible. I just top it off about once a year. The mechanic could possibly be right, maybe the final drive bearings get sloppy or something. There have been others with the same problem.

[zoe60]

Of course, it is pretty easy to replace the seal and I would start there for sure.