e40d..overdrive button flashing!
i got a 97 powerstroke and my overdrive button will switch on every once in a while and blink..and when it is blinking my truck will shift so hard it feels like im getting rear ended..then it will go off and come back on sometimes the same day or a couple days later..i went to one tranny shop and they said its detecting slippage and putting more pressure in the lines..idk though any suggesttions or people who are familar with this problem??
Flashing OD light can also be a rear speed sensor, but with the shifting you are talking about it sounds like a tranny issue.
Try cleaning the connections on the rear speed sensor, its on top of the rear axle.
Try cleaning the connections on the rear speed sensor, its on top of the rear axle.




, he said i only needed a new lock-up but with 300k+ on it should just do everything