LOL..

So if it won't go into 4th, you kick perf off and then back on and it'll drop right in huh? That's funny to me because I have had that in my car (192K miles). I've chatted with Dave and some other trans shop owners on the subject. No one has much info about it, potentially sloppy worn out valves in teh valve body.

In my case..my trans is pretty shot. Fluid looks like muddy million mile engine oil and well.. yeah. It's bad.