My over drive button is acting finicky... 2001 250 7.3. It turns OD off in park but I have to play with the shifter in other positions. When it does turn on it seems like it works ok loose wife??

 

Not a loose wire, a worn through wire.

Take the cover off the steering column. Inspect the wires where they enter the shift handle. One or more of the wires are worn through. Either fix the wires or replace the shift handle.