Re: O/D light flashing
I had a 1999 Mountaineer with a 4.0L SOHC and a 5R55E trans that was doing this. The Ford dealer said to restart the vehicle, hit the O/D OFF button and take it for a drive. If the O/D OFF light no longer flashes it's an issue with the O/D OFF button. If the light still flashes the trans. has an internal issue.
Master ASE Certified L1 Chrysler Technician- still a Ford fan at heart.
1964 Thunderbird Hardtop- Chantily Beige- 390 FE 4V V8-Uncle's Car
1966 Thunderbird Convertible- Red- 390 FE 4V V8- Uncle's other car- waiting for paint and body work!!!