I have 1997 Heavy Duty F250 w/ 7.3 Diesel. Today I noticed on my shifter lever there is a button that shifts on/off the O.D. . Today that light is steadly flashing on and off. Anybody got any idea of what could be the problem?

 

Get a trans shop to read the codes, the trans is probably slipping. Not all code readers will read trans codes.

 

There are about 50 different things that can make the light flash. Each one of them will store a code in the computer's memory. The ONLY way to know what's wrong is to get the codes read.

 

Thank you to all that send in comments to help. Problem was the MLPS switch. I replaced the switch and all is well now...light has stopped flashing.