Ok, What have I done now... (904 problem?)

My brother has a saying, "If you hear hoofbeats, think horses not zebras." In other words, don't over-think the problem. If it was fine before you changed the filter & fluid but not so immediately after, start there. This is a good time for k.i.s.s. Too often people panic & start to reinvent the wheel when it comes to certain things on a car. Transmissions are complex, but most of the time the problems surrounding them aren't.

With regards to the ATF types vs trans failure; I'm an ASE Master Technicain for over 25 years & a shop owner for the last 5. In addition to my own experience I have many friends who specialize in transmissions & have talked to reps. & engineers from major oil companies(E/M) & they all say the same thing. The type of ATF you use WILL NOT cause trans failure by itself. It may change shift firmness somewhat, but minimally. Most customers wont notice. If it fails after a change there is some other underlying pre-exsisting condition that would have cause failure or problems soon anyway. Worn parts, bad seals etc.