98 OD light blinking

My Ranger's OD light comes on blinking every other time I drive. The shift from 1st to 2nd goes hard when this happens. My dealer said that the code wasn't in the manual and they could not make it fail. It seems that it happens more ferquently now. Sometimes when I'm going under 40 and others only when I reach turnpike speed. Any ideas???

I have a 98 Explorer with the same problem. The light came on once before but I didn't notice any problems at the time and the light just stopped blinking. Now it is starting to shift hard but only occasionally.

Well the dealer finally found out what the trouble was and it turns out to be a bad solenoid for the torque converter. My extended warranty should of covered it but the company Pro-tech is in chapter 11. The cost wasn't to terrible $275.00. Thanks