I can't say that I have ever seen a hole like that. Does it go through to the outside? Meaning if you had the pan on it could you put your finger inside? Are the edges sharp like something has punctured it?
Either way, if it holds fluid then I would not think this hole is causing your slipping issue. The transmission itself is not under pressure. Your oil passages and things are what are under pressure.
That leads us to needing to know what codes are in the computer. One this vehicle they are going to be pretty basic but they will at least point us to a solenoid issue or a mechanical issue.
I suspect you are going to have an internal issue that will require a rebuild and in this case, it may be a good idea to just replace the unit with a reman unit. That way, you take care of that hole as well.
I attached the transmission code descriptions for when you pull them. Let me know what you find and we can go from there. Thanks
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Wednesday, May 26th, 2021 AT 6:11 PM