I too have had the bolts and nuts loosen and have the entire jackshaft "flop" around. I replaced the original nuts with nylon and loctited them but Now I have a vibration and the belt slaps like crazy.. it possible I have a bent shaft. I'm not sure with the shaft loosening that the belt was stretched or burned a flat spot. I just can't beleive this is as common and no requirment for the dealers to check them with maitanence checks.:confused3: