I JUST DISCOVERED THAT THE LEFT REAR RIM ON MY 2007 BMW 328 CONVERTIBLE IS CRACKED. MY CAR HAS LESS THAN 38K MILES ON IT. THE TIRES ARE 225/45 17ќ RUN-FLATS. I HAD FOUR NEW TIRES PUT ON ABOUT 6 MONTHS AGO. I GOT THE LOW TIRE PRESSURE WARNING LIGHT ABOUT A WEEK AGO WHEN I STARTED THE CAR. I CHECKED, DIDN'T NOTICE ANYTHING, AND RESET THE TPM SUCCESSFULLY. SINCE IT WAS A COLD MORNING, I FIGURED THE SENSOR WAS JUST REACTING TO PRESSURE CHANGE DUE TO THE TEMPERATURE CHANGE. A FEW DAYS LATER, IT CAME AGAIN. I DECIDED TO CHECK, AND FOUND THE PRESSURE WAS DOWN TO ABOUT 25 PSI. I FILLED THE TIRE TO RECOMMENDED PSI. I DROVE ABOUT 260 MILES ON SUNDAY, MOSTLY FREEWAY SPEEDS. WHEN I WAS ABOUT 30 MILES FROM HOME, THE WARNING LIGHT CAME ON AGAIN. AT THAT TIME I WAS ON A FREEWAY, GOING ABOUT 70 MPH. ONCE I GOT TO HOME, I FILLED THE TIRE (AGAIN IT WAS ABOUT 25 PSI), AND THE WARNING STOPPED. YESTERDAY THE LIGHT CAME ON, AND I TOOK IT TO MY LOCAL TIRE SHOP. THEY DIDN'T FIND A PUNCTURE; BUT REMOUNTED IT AND FILLED IT. I DROVE HOME, AND A FEW HOURS LATER, THE WARNING CAME ON AGAIN. THIS MORNING, I TOOK IT BACK TO THE SHOP, AND THEY AGAIN REMOVED THE TIRE. THIS TIME THEY DID A VERY CLOSE INSPECTION AND FOUND THE CRACK IN THE RIM. THEY ARE ORDERING ME A REPLACEMENT RIM. FROM WHAT I HAVE SEEN ON THE INTERNET, THERE SEEMS TO BE A PROBLEM WITH THE BMW RIMS AND RUN-FLAT TIRES. THIS IS DEFINITELY A SAFETY ISSUE, IF THE RIM WOULD HAVE A CATASTROPHIC FAILURE WHILE THE CAR WAS TRAVELING AT HIGHWAY SPEEDS THIS COULD BE DEADLY. *TR
