I had the same problem about a month ago...at about 64,500miles. I was stuck in horrible Washington DC Beltway traffic and then all of as sudden I started getting the hard shifting and O/D light flashing plus the CEL on. It turned out to be a bad torque convertor. I had it replaced and all is fine.
Luckily I purchased the Ford ESP...it finally is paying dividends.
Jefe
99 Mystique LS
