NHTSA Complaint #10442038 — 2008 HYUNDAI SONATA

PURCHASED DEMONSTRATOR CAR WITH APPROXIMATELY 2,500 MILES FOR NORMAL USE. REAR DISK BRAKE NOISE AT 15,976 MILES REQUIRED BOTH REAR BRAKE PADS AND ROTORS TO BE REPLACED UNDER WARRANTY. SAME PROBLEM HAPPENED AGAIN AT 33,356 MILES, AGAIN REQUIRING REPLACEMENT OF PADS AND TURNING OF ROTORS (THIS TIME IT WAS NOT COVERED - CONSIDERED NORMAL WEAR ITEMS). ONCE AGAIN, AT APPROXIMATELY 52,000 MILES, LOUD GRINDING FROM THE LEFT REAR BRAKE REVEALED THAT BOTH INNER AND OUTER PADS HAD BEEN TOTALLY SCRUBBED OFF WITH LIGHT METAL TO METAL CONTACT, WHILE THE RIGHT REAR PADS STILL HAD GREATER THAN 50% OF ORIGINAL PAD THICKNESS. THE CALIPER SLIDES OPERATED SMOOTHLY AND WERE WELL LUBRICATED AND SEALED, AND THE PAD SLIDES WERE DIRTY WITH BRAKE DUST, BUT NOT CORRODED OR BLOCKED WITH DIRT. THE PADS APPEARED TO HAVE BEEN EXPOSED TO HIGH HEAT. I REPLACED THE PADS TO FINISH MY TRIP AND UPON RETURN IT WAS APPARENT THAT THE NEW PADS HAD BEEN DRAGGING AS EVIDENCED BY A STRONG SMELL AND GLAZED APPEARANCE. IT DOES NOT SEEM NORMAL FOR THIS CONDITION TO HAPPEN - THERE WAS NO GRINDING OR ABNORMAL NOISE OBSERVED DURING THE MOST RECENT EVENT, UNTIL PULLING INTO OUR DESTINATION, WHEN IT WAS VERY LOUD. APPEARS THAT THE CALIPER OR CALIPER PISTON IS STICKING TO KEEP THE PADS IN CONTACT WITH THE DISK, THUS OVERHEATING AND CHALLENGING THE BRAKE PAD LIFE. THIS SEEMS TO BE ONLY ON THE LEFT (DRIVER'S SIDE) CALIPER. HYUNDAI DISCUSSION FORUMS HAVE INDICATED THIS IS A COMMON PROBLEM THAT HYUNDAI IS NOT FORMALLY ADDRESSING. I WILL TAKE THE CAR TO THE DEALER THIS WEEK, BUT WANTED TO REGISTER WITH NHTSA SINCE IT IS A BRAKE ISSUE WITH SAFETY IMPLICATIONS. *TR