No shift
Hopefully some one might have a clue where I should start. Bus trans will not up shift. Old girl has a 3208 with Allison mt 647& stone Bennett air shifter. Has never failed not to work but now will n...
Forum Discussion
I have an Alllison MD 3060 so I don't know if this answer is applicable. Last year I got a do not shift light after a sensor on the tranny became disconnected. It would go in first and reverse but when it tried to up shift it went to a do not shift fault. Maybe you have a similar sensor.
