I was under the impression that the driveline clunk when shifting from drive to reverse was normal on my 91. It has always done that. If it bothers you let the truck roll a couple inches in neutral when your shifting and the clunk will go away3fe in a 91. New to me. 146k white, Was at the shop this week and replaced diff fluids, valve cover gasket, adjusted valves, exhaust and intake manifold gaskets, radiator, hoses, thermo, cap, and more. Next week driveline gets checked for the clunk when shifted to reverse, and tune up. Power steering pump from dealer is 600 bucks, that is going to wait a bit, just a slow leak. ordered all oem tune up parts -