Transmission or sensor problem?

I have an '03 Taurus SE V6 3.0 182 CID VIN 2 with 79,000 miles, when I'm driving it above 50 miles an hr or more in OD the it randomly shifts back and forth between OD and D sometimes causing the engine to stumble it almost feels like a miss but I'm watching the Tac bounce back and forth from 2000 to 3000 rpm and even when I let it coast down hill it will still shift back and forth like that.....could this just be a sensor misread or is it the beginning of something more serious.......:frown:



P.S. I just took it down to the local AutoZone and had them put it on a scanner and its not kicking out any error codes

It could be an issue with your speed sensor, but that usually throws a code.

It could be in input shaft, intermediate shaft, or output shaft speed sensor issue. These sensors will not show up with a general powertrain code scan. It requires a scan tool with the transmission software to read these codes. Pressure issues in the transmission will also be available via the transmission software enabled scan tool.

-Rod