Bought a repo'd 2007 with only 10,000 miles on it. Took it into the dealer for its 15,000 service and both rear tires were out of round and one had humongous flatspots on it. I had been warned that Prius had tire issues, particularly relating to mpg. The service crew told me they'd never seen a Prius tire in such a state. I cant see how a non-drive wheel can have such wear problems unless the brakes are mis-functioning.( I hear and feel no evil whilst driving) these are TOYO tires and apparantly OEM. Any input appreciated. This is the only issue I have with my Pious.