vibration in rear end

what would you think if I replaced both u-joints and it clunks from reverse to drive as bad as before I changed them? i replaced the u-joints twice... still clunks and still vibrates. any thoughts? i have had this truck for 4 months now and it has not once given me a smooth ride. thanks for any input

Some clunking when going from reverse to drive is normal.

hootymo,

clunk from reverse to drive COULD be indicator of impending sun gear shell failure. of course when this happens, you will lose Reverse, 2nd and 4th (O.D.). just ensure that you come to a complete stop BEFORE shifting from Reverse to Drive - no sence in increasing possibility of failure.

People need to understand that when you go from drive to reverse, all normal slack in the drive train will reverse.

This is completely normal. No drive drain is perfectly silent.