[jumpingjack66]

Before everyone starts tearing there trucks apart can i sujest something? If you excelarate from a standing start and your axil begins to wrap as they will do on 4000 pound vehicles the only thing that will stop the wrap is the bump stops made of rubber . These bump stops hit and correct me if im wrong here but the hit the underside of the leaf springs correct. What does that sound like? Its a thunk guys and girls and it is normal. Try this, put a small video camera under your truck somwere and do some stops and starts to see how much your rear end moves. Wraping is normal and only preventable with a large expendature of money on aftermarket parts. What you all should be concerned about is if there is any side to side movement or any turning movement lateral to the direction the truck is going. Guys these are trucks get over it. Im less concerned about clunks and thunks then i am about the damn ABS brakes not working on these pos gm products. Look, if its a thunk or a clunk the only trhing you can do is mash the gas and use it till you brake it. Replace whats broken and do it again...jj