my 2000 explorer is driving me nuts!!!!

here is some info, I hope someone can help out.
I have a 2000 Ford exporer Sport, SOVC,Auto.
My transmission has been missing between second and third gear. I feel it shift from first to second, then it revs up about 700rpm before hitting third, after that no problem. My second problem is that tonight my over drive light started flashing for some reason, I know a bit about cars but this is comletely foreign teritory for me. My third and final problem is my check engine light. I get it looked at, there seems to be nothing wrong, I get it turned off and then a week later it turns back on. don't know why, don't know the code but I had a trustworthy machanic working on it and he could not figure it out. There seems to be some knowlegeble people on this site, so please help if you can.
Thanks a lot.
bob

It's possible the transmission mechanical problem is caused by "bad information" between the engine computer and the transmission, which has electrical characteristics. You could nail down the Check Engine Light first (spending money), hoping that will fix the transmission problem.
Personally, though, I suspect the transmission has its' own problems. A 2000 should already have Mercon V synthetic fluid. I recommend that fluid be completely flushed out at 50K intervals. If anybody has put anything lesser than synthetic, I recommend a 25K interval. Have you done that? Hows the fluid level (Engine warmed up and running, in Park)? Does the fluid have a nice oily smell and a good reddish color or does it smell burnt and have a brownish, less-than-red color?

take it to dealership, have them check it for codes it could be the rear abs speed sensor, I used to work for ford and i've replaced a pile of speed sensors. They do funny things, its on your rear axle

It sounds like the same problem i am facing right now. Please post what you find out and i will do the same. The first shop said it looks like a bad clutch in my third gear??!! About 1800.00 to fix.....i will keep researching.

That sounds about right. If the same generation, you have a 5R55E. First is the low/reverse band. Second is made from the combination of the low/reverse and overdrive band. This was the change that was made to the 4R55E to add an extra gear. Third is the intermediate clutch. Fourth is the high clutch to which the OD band is added to give 5th or overdrive. If the band snaps, it will skip to the next gear eventually. This isn't a hard home project. Transmissions are easy to work on, I just hate taking them out!

also, the 5r55e OD soleniod isn't known for its reliability. this would cause the delay in getting to 3rd, and if driving at high speed/load (85+), slippage in 5th and a blinking check engine light. Next time it lights up, look at your RPMs. higher than normal? OD solenoid is failing.