I don't use any sealer on transmission pans. Just have to make sure pan rail is nice and flat. I use a ball peen hammer on the bolt holes to take the "depression" out that is made by the over tightening of the pan bolts.
Never even knew that stuff existed. I guess I probably shouldn't use anything by the responses. I just have a slight suspicion that the former gasket was contributing to a leak. Thanks for the responses, Carmine.
It's a powerglide thing. I put new seals and pan gasket and if you let it sit, it eventually spews fluid from every pore! I keep a large pan under it at all times! My 69 Chevelle w/powerglide does the same thing. (and I've heard many others with the same problem)
Yes, a TH400 transmission. I'll have to take a look at a schematic and see where this pump "O" ring is located. If it requires removing the transmission, that will have to wait until I'm ready to change the torque converter, Carmine.
You answered your own question why. If you start the car at least once a month, the fluid stays in the torque converter where it belongs. Let it sit for a long period of time, the torque converter drains back into the pan, and will overflow out the vents. My 1963 Chrysler did the same. It is really not leaking, it is just reminding you that it misses you.....