chattering sound from drive train

[mlozzi200478]

while driving down the road,i lift the accelorator,then suddenly i hear a chain like chattering,it sounds like its coming from the drive shaft,could this be a universal joint,or does an 89 300ce not have any,i see rubber discs between prop shaft,what could cause this noise when i lift accelorater. when i reapply accelorator the noise disappears.you only hear it when the cars slowing down.itsounds as if something is scraping the prop shaft??