Truck Repair: 4R70W ford transmission pan leak, hairline crack, phil ford

Question
As this question is related to ford maybe you can help.I need a second opinon. The pan leaks in the corner just below the dip stick tube,I have ruled out the o-ring in the tube and just about ruled out everything above the leak as it is dry. I replaced the original factory gasket with cork but the leak is still there, would it be in my best interest to replace the pan and go with the oem gasket.There is no evidence of pan damage,but I am at a loss as to my next move the leak is not bad just a nuisance,Thanks for any help and have a happy new year. Phil ford

Answer
Hello Philip,
I would get down there, and use some brake parts cleaner to clean it off real good, and look for a hairline crack, or some imperfection in the case casting.
If you are convinced it is the gasket leaking, an RTV gasket might seal where the cork won't.
While the pan is off, clean it up, and lay it on something flat and smooth, like the kitchen counter, and see if it is bent, like where the bolts go. Tap them flat.
Good luck,
Van