Leaky transmission

Shift shaft seals only leak when the car is sitting still and shut off. Thats the only time the fluid level is up high enough to get there. Think about it and you'll see that the fluid level is fully in the pan when the car is running, sssooo,, I'd say you have a bad connection at the cooling lines, or a leaking pressure port plug, cause it sounds like you're telling us that it leaks, while it's under pressure.
My 2 penny's worth!
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