Stock TH350 Pan

[geunther]

From what I understand no TH 350 came with a drain plug from the factory. The confusing part about this pan is that it has a date stamp consistent with GM date stamps. Also the date would be consistent with coming on the truck originally but I guess that cannot be accurate.

Anyway, I cannot get the thing to seal no matter what. When I tighten it enough to seal (about 14 foot points), it pushes the gasket out as you can see in the pic. The pan has a ridge about half way on the flange between each bolt. I am wondering if it is splitting the gasket. I am considering ordering another pan without the ridge but wanted to get your input first.

I had both surfaces spotless.
Rubber gasket