Kerrmudgeon

The last drive I drove my 56 I took it on a cruise of about 100 miles all around, and on the way home I gave it a bit of hell on the highway to clear any carbon out of the old 265, dropping it into passing gear until it shifted by itself at speed. When I got it home it promptly bled to death.....dripping trans blood all over the floor....lots of it.
Q. Is there a seal or gasket that would be suspect as the likely culprit? I was pretty disheartened and haven't climbed under to inspect. What should I be looking for?
BTW.....I had the trans shop take it out and put all new seals and gaskets and adjust it a few years ago. I sure didn't expect to have any problems.

I've been toying with an overdrive 700R or 200R for a while now but just wondered if it might be an easy fix to stop the leak?
thanks.

R66

Only a few leakage points, pan gasket, dip stick o-ring, front seal, rear seal, and if applicable the vacuum modulator.
If it never shifted - vacuum modulator. If it shifted normally but just dumped the blood, I would look at the front seal.
Just a guess until the experts come around.

ron

Nowhere Man

If it's like the later mid year glides the speedo cable attaching point can leak.

John BX NY

I'd read this. If the torque corverter dumps it's fluid it pukes out all over...

http://www.earlycorvettes.com/corvet...v5n4PGleak.pdf

ohiovet

56 and 57 PG do not have pan gaskets or vacuum modulators so no leaks there.

My 57 PG leaks lots of trans fluid when it sits for a month or 2 due to the convertor leaking down.
During the driving season it does not leak a drop.
I have wound it up pretty tight recently and have not experienced any additional leaking.

Sounds like it is time to get under the car.

J.Moore

You may have caused fluid to puke out the vent after you pushed it on the highway. Check and see how low the level is. The torque converter cover has a huge o'ring around the outer ring near the bolts that seals it to the converter body. If trans was rebuilt a few years ago all the seals and o'rings should have been replaced, but they can still leak now though.

This is a cast iron PG isn't it? Spray it off with can of Brake Clean and blow it off if you have air, clean it up best you can, fill it and drive it again. Sometimes it's hard to tell just where the leak is from.

csherman

also shut the car off in gear

Nowhere Man

What is the reasoning behind this? Does it apply to all powerglides?

domenic tallarita

Yes on the vent, that is it's job.

Dom

J.Moore

On a normally trouble free auto transmission there should be no fluid coming out the vent. If fluid does continue to leak from vent it is usually a sign of an internal problem of some sort.

But,,, too much fluid from the start can also cause fluid out the vent when there is nothing wrong internally. Sometimes just 1 qt. overfull can cause it.

domenic tallarita

True and I agree. one other thing is that to low will also cause it to get hot and blow out oil , especially if the clutches start slipping because the hyd pressure gets low and lets them slip. In the day of that transmission, whenever you got gas the hood opened and the attendant checked all the fluids. That's what saved most of us that beat the old mans car to death on Friday knight. Now things are different. In the last year two of my friends 700R4 transmissions threw oil out of the vent when they were pulling small trailers on a hot day. washed them and filled them and all was normal again. Also both had transmission coolers other than the radiator cooler.

Dom