Transmission mystery

[Althing79]

Ok, this morning I posted a thread about swapping out my transmission and have now realized I do not have the large amount of money it would take to do so, so naturally the next and hopefully substantially cheaper route would be to rebuild it. My problem is diagnosis. First off, I used to run an Apten chip in my truck and when it started acting funny (wouldn't shift when RPM's were maxing out) I took the thing out. Unfortunately it's been acting funny ever since I took that out too. Over time it would continue to max out the RPM's and not shift and then it changed to just shutting off overdrive out of nowhere and it could not be turned back on. Then I noticed that it would miss random shifts, and also occasionally started off in what I could only imagine as second gear. Well a couple of months ago it just crapped out on me totally. I was at a stoplight and all of a sudden it wouldn't go forward and just shut off the engine. Every time I would turn the car back on it would start but as soon as it was put into gear it would shut off again. I don't want to buy all kinds of crap that I don't need to rebuild my engine. I've done tons of work on other parts of cars but transmissions are a bit of a mystery to me. Does anyone have a clue as to what could be the main problem? Should I buy a whole transmission rebuilt kit and a shift solenoid and is there any other parts that usually go out and need to be replaced that wouldn't be included in a rebuild kit? My family is a bunch of jerks and won't help me and nobody I know knows anything about it. Any clues or advice would be amazingly appreciated. Thanks, y'all. '99 Ford Explorer Sport with a 5R55E tranmission.

 

[manaen]

you may not need a rebuild it could be as simple as a blown valve body gasket, among other things.