Hey i just got a 1991, f250 diesle with an automatic, and it has an overdrive cut off switch. The switch always blinks while im driving around wether the over drive switch is on or off. As soon as i stop it stops blinking. Is this normal? if its not, does anyone know whats wrong with it? THanks
Andrew

That's an indication of a detected fault in the trans, and is a bad sign. The early e4od's (which you have) are garbage, and tend to fail, esspecially behind the diesel.

Go here (http://www.thedieselstop.com) go into the forums, and look at the 7.3 idi forum. They will be able to tell you what to do.
~John