I WAS EXITING THE FREEWAY AND STARTED TO TOUCH THE FRONT WINDOW BUTTON DOWN BUT IT WAS THE REAR WINDOW BUTTON AND IMMEDIATELY THE WHOLE CAR STARTED THIS SHAKING AND VIBRATING. I WAS SHOCKED AND SHOOK-UP BY THIS EVENT AND IMMEDIATELY PULLED OVER TO THE SIDE.LUCKILY, DOWN THE ROAD A BIT, I SAW A BUICK DEALERSHIP AND PROCEEDED TO IT. THE SERVICE MGR. TOLD ME BUICK IS AWARE OF THIS PROBLEM WHICH HE CALLED "WIND ABATEMENT".ONE OF HIS ASSOCIATES EVEN ASKED ME IF HE COULD COME WITH ME SO HE COULD WITNESS THIS EVENT. SO WE DID GO BACK TO THE FREEWAY,LET REAR WINDOW DOWN, AND HE WITNESSED IT HIMSELF.THE BUICK DEALER DENIED ANY DEFECTS IN THE CAR AND ADVISED ME TO CRACK A FRONT WINDOW ABOUT AN INCH, THEN LET THE REAR WINDOW DOWN. THIS WHOLE EPISODE HAS LEFT ME IN A STATE OF SHOCK AND NOT KNOWING IF THIS VEHICLE IS SAFE TO DRIVE.