I put a new driver side axle in a few years ago and had problems getting it to seal properly. AAMCO put like 5 seals in it before telling me they give up and not to bring it back. I've been checking the level regularly and usually just refill the trans at each oil change. I haven't had any mechanical problems yet, but the mess it leaves on the ground is getting annoying. I've been thinking of pulling the trans for a rebuild, but whenever I'm on the highway I really want another gear. (My six speed GM cars have ruined me for the Max's five speed)

TLDR: Should I rebuild the stock 5 speed or go through the hassle of a 6 speed swap?

 

either seals are installed incorrectly, or you could have a bad diff carrier bearing, or have you checked the axle is the right size

 

I would pull the axle, take pics of the hole where the seal is, perhaps someone can tell if it looks right.. Also might want to confirm the axle is correct as was suggested.. I remember when I did my clutch that the driver's axle has to pop in to be fully seated.. Do you know if the passenger side axle was ever replaced? Maybe that install could have caused an issue with the carrier bearing that is not allowing the driver axle to seat properly.

 

I mis-spoke in the first post. It was the passenger side axle I changed years ago that has been leaking. The driver side axle was replaced last year and is fine so far.

After the first couple seals, AAMCO blamed the problem on the axle. I pulled it and swapped it at O'Reilly's for another one. AAMCO installed that one with a new seal and still leaked.

 

Yea the passenger side axle is pretty simple; as long as the splines for the diff are correct then the axle is correct. If it's just the passenger side I bet the seal is wacked.

 

Put it with RTV that's compatible with manual trans fluid around the outside. For whatever reason on my last MT, the passenger seal could be pressed in with almost no pressure so it leaked around the outside of the seal. RTV stopped it.