I have one of those, I thought it was off a chevrolet. I also have a 839754 - 777 and I'm wondering what it is. I know the ring gears are not interchangable, 6V to 12V and I seem to remember reading somewhere that they are not interchangeable Chevy - GMC. Usually the ring gear can be turned over if the teeth are worn, if it's simply not engaging well.
Last edited by ole5ogmc; 04/18/2011 5:15 PM.
