jnj55024

Hi everyone, I'm new to this forum and just bought a 57 Super 88 371 with 4 speed hydramatic. It is leaking pretty good out of the front end of the tranny. I am assuming it has a front pump seal and I'll need to drop the tranny out of the car. Any tips on dropping and replacing this seal? Anything else I should be doing while it's out? Seems to shift real well, maybe a bit lurchy from 2 to 3 but otherwise smooth as silk.

I have a CD shop manual coming. I already ordered the front pump seal, rear tail shaft seal and trans pan gasket from Fusick.

Olds64

If you need other hard to find parts for your transmission look at Fatsco. They are in NJ.

Welcome to the site.

jaymann

I've got the same tranny in my 56 Olds, and another one sitting on my shop floor from my 56 Cadillac.
I haven't tore into either yet...the Olds leaks too...
What I can tell you is be careful...that tranny weighs a ton! I can barely move the thing by myself. I can pick up a TH350 no problem...I can't lift the 4 speed!!
I wouldn't want to be pinned underneath that thing.

jnj55024

Thanks for the heads up on the weight. I think I have the parts required from Fusick.

I am a pretty good mechanic but have only installed and removed trannys before. Never replaced shaft seals.

Can I do this myself? Any special tools required other than a good floor jack to get the trans out from under the car?

I am assuming I'll just pry the seal out. I read about a trick where you drill and install a few sheet metal screws in the seal to pry on if it is stubborn and wont come out easily.

redoldsman

No way I would try that with a floor jack. I would definitely do it with a transmission jack. That thing is cast iron and has to weigh several hundred pounds. It is a beast. I know the old Buick Dynoflows had a front pump o-ring they used to replace. I don't know about the hydramatic. As jaymann said, be very careful. Good luck with it.

Olds64

You have to be careful with automatic transmissions. If you pry out the shaft seal and damage the shaft or the seat for the seal then it may continue to leak even with a new seal. Plus, I wouldn't do any drilling on an automatic transmission. Any metal shavings could get into the valve body and destroy your transmission.