i have a 1988 bigbear 350 4x4 been riding great i already replaced front u joints but here lately been feeling and hearing a clunk at low speeds and low speed turns underload i know its comeing from rear drive.i never replaced rear u joint still factory could this be my problem is that a sound a bad joint would make.low speeds underload its like a clunk clunk,clunk clunk,clunk clunk, checked bearings in rear theres no play at all.i can feel the clunk in left foot rest when it does it almost like something forced then pops.i figure its either the u jiont or the transfer case gear lash out of adjustment.the bike doesnt skip or lake power while makeing these noises.can someone tell me if they have had this problem and what it was.and is this sound typical of a bad u joint