I have an 88 chevy 1500, 4wd.
It was making some noise when shifting from park to reverse or to drive. It also made a knock when shifting at about 15mph.
I checked the rear u joints and they seemed fine. I brought it to a tranny shop who said it was play between the transfer case and rear differential. With the u joints being okay, I assume it is the rear diff. What would wear to cause the knock? Do i need to replace the entire differential? Would I be better off replace the entire rear end with a used one?