School me on trans basics

I didn't see any cracks on it with just the inspection cover removed. can it be cracked/shifted at the crank?

They can crack right around or even directly from one to the next bolt hole at the crank as well as from the center out, like you might see with the cover off.
The big problem is if it gets bad enough to take out the trans pump before it gets caught, and an off balance problem like you described with heat changes and (sometimes) contacting the block could very well indicate that this is exactly what is happening.

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