[gumby79]

Many of the car manufacturers have gone to run flat technology tires. The reason for running the ultra stiff sidewall run-flat style Tire is to delete the weight of a spare tire. Unfortunately the downside is the tire doesn't deform until it has consumed itself due to the extra heat of the air not supporting the weight the sidewall is doing it insted. Every Tire I have stopped on the side of the highway to help someone stranded that has been one of these run-flat Technologies has disintegrated before the driver was aware that they had a low tire and then there's no spare tire I ruined rim and they're still stuck on the side of the highway. The only ones I've seen survive a picking up a nail have had the air monitoring systems that have become A DOT safety item, when the air pressure monitoring systems gained safety item status the aftermarket air pressure monitoring systems were pulled off the market unless they can pass the DOT testing procedures making them unavailable to vehicles like mine that don't have factory installed safety equipment.
On the bright side it only cost you 11 MPG instead of that plus a tire.