Overdrive issues

I have a 94 t-bird lx with a 3.8 and just started to have the overdrive light flash. I only flashes after I try to drive and then the car also seems to take forever to shift to 2nd. I also have hard shifts after actually getting to 2nd. Any idea would be great.

I have replaced the speed sensor and the transmission speed sensor and still have the same problem. This was after I had a tester put on and found codes 637 and 639? Any ideas would be great, because I also have a airbig issue flashing at the same time. Computer?

Changed out the computer still the same issues???????

Sounds like the drive bands are dying. Nothing short of a rebuild will fix that. I had that exact same car, with a very similar issue. I just got a low mileage junker tranny and it worked fine until I sold the car. If you confirm it is the drive bands, you can throw some Lucas in there and that will usually give a few hundred perhaps a few thounsand miles of life, won't hurt it at this point though. Could be something else, but sounds like the bands.