[seningen]

I'd ask why it was rebuilt in the first place and what exactly was done.
I would do it in a manner that wasn't accusatory -- just like
hey dude -- I'm trying to figure out what is going on and I need
to have a baseline.

Clearly this isn't normal.

Any idea what fluid is in it? Does it have the proper amount?

It's possible there was debris in the oil pre-rebuild and it didn't all get cleaned out
and its gumming up the valve bodies.

I'm not sure if something like a Duramatic can read the actual codes and
see if the tranny can tell you what it is unhappy about.

Mike