JohnCalifornia 
2007 Toyota Sienna Minivan XLE 7-Passenger 4dr Minivan AWD (3.5L 6cyl 5A)
Tire Trouble
 This is our second Sienna; our 1998 was fine.  We've had the 2007 model for two years now, and it's had a lot of trouble with the run-flat tires.  A couple of flats, and the air-pressure warning light comes on way too often.  Today I took another flat to the dealer; the service department said "you're not supposed to just replace one of these at a time -- we should do all four. Otherwise, if the differential fails or the transmission fails, Toyota won't cover it under warranty."  So -- throw away 3 good tires (only half worn) and spend $1000 on new run-flats, or Toyota won't honor the warranty?  Ridiculous.  Also, this van gets at least 20% worse mileage than our old one.  Disappointing!