2001 LEXUS IS 300 Suspensionfrontcontrol Armlower Arm Problems

PASSENGER SIDE CONTROL ARM MADE TAPPING SOUND. TOOK TO PARK PLACE LEXUS, PLANO TX - CAR IS UNDER WARRANTY SO THEY REPLACED FOR FREE. THEY TOLD ME THAT A RUBBER GROMMET/GASKET WAS MISSING AND THAT METAL HAD RUBBED METAL UNTIL SEVERE RUST DEVELOPED. ONLY ABOUT 1 MONTHS LATER THE NOISE IS BACK AND EVEN MORE FREQUENT THAN BEFORE WITH ITS "PEK" "POP" "TIK" "TAP". ALSO THE SUSPENSION HAS A TREMENDOUS VIBRATION IN IT, WHENEVER I TRAVEL OVER THE SLIGHTEST CRACK IN THE PAVEMENT - IT FEELS LIKE SOMETHING IS PARTIALLY ATTACHED AND SHACKING FROM THE CHANGE IN SURFACE. ITS A VERY HEAVY AND SUDDEN THUMPING. WHEN THIS OCCURS, EVEN THE STEERING WHEEL ADJITATES TO THE POINT IT CAN BE SEEN - ITS A TREMENDOUS FLEXING. PARK PLACE HAS TOLD ME BEFORE THAT I AM "WASTING" THEIR TIME AND I JUST EXPECT THEM TO "THROW PARTS." THIS HAS BEEN THE MOST...