RUN FLAT TIRES ARE UNSAFE AND TREAD WEAR LIFE IS EXTREMELY SHORT. 2004 TOYOTA SIENNA XLE AWD LIMITED HAS OE DUNLOP SP SPORT 4000T DSST 'RUN FLAT' TIRES. CAR HAS 19,000 MILES AND ALL 4 TIRES ARE COMPLETELY BALD. CAR HAS BEEN MAINTAINED BY THE DEALER PER MANUFACTURERS INSTRUCTIONS. 'RUN-FLAT' CARS DO NOT HAVE SPARE TIRES, JACKS OR TIRE WELL FOR STORAGE, SO THERE IS NO WAY TO SWITCH TO REGULAR TIRES WITHOUT LOSING THE REAR CARGO SPACE. I CANNOT AFFORD TO LOSE THIS SPACE AS THIS IS WHY I PURCHASED THIS VEHICLE. NEW RUN FLAT TIRES WILL COST ME WELL OVER $1100 PER YEAR AT THIS TREAD WEAR RATE. THE COMBINATION OF THESE TIRES WITH THIS MINIVAN SEEMS TO BE A SERIOUS PROBLEM. IT POSES A HUGE EXPENSE TO REPLACE THESE TIRES REGULAR AND IS A SERIOUS SAFETY HAZARD TO A CLASS OF OWNERS WHO GENERALLY HAVE INFANTS OR YOUNG CHILDREN. NHTSA SHOULD ACT TO REQUIRE TOYOTA AND DUNLOP TO RESOLVE THIS ISSUE SATISFACTORILY. *JB