I'm at aloss to figure out a knock in the rear end. Usually when good and warmed up I get a knocking in the rear end. It ONLY happens when coasting and occurs in a straight line or turning. It feels and sounds like a hub, which is what I thouht it was till I brought it in to a fwd shop. They it to do it but could not find anything. They said the rear had been overfilled, did a "posi service" and refilled. Somethimes it doesn't do it (usualy if there is a mechanic nearby) but I can usually get it do do it aftre a few hours of high speed driving. When really bad it will do it right down to a stop and when rolling very slowly you can feel it binding as it knocks. A friend seems to recall burbs having problems with rear bearings going ot of round but it seems like if that ws the problem it would do it all the time. Any advice greatly appreciated.