As Freddy Flinstone grouses: "'Uhh Boy!'',that thumping turned out to be the front passenger suspension bushing & ball joint seals,the part will be around the 0.00 mark,I may go back for this since it's a special part.The tire rotation went without a hitch,rides very well again,glad I did it now.My brakes need some work,wil go to a Midas type store for that,hell with GMs' flat labor rate jazz.Over all,i'm batting about half way for now.Oh yes,the thumping is more pronounced now,maybe the tire inflation was down,or,just from the rotation.