Hi There. I just got back from my Mazda Dealer for the 4 Year Maintenance Service and they mentioned that the rear rotors need to be replaced within the next 6 months. They sanded it down last year already and did the same yesterday. But they said that it had to be replaced at a cost of almost $450. I think they also mentioned that the rear brakes will be replaced at the same time. But the paperwork that they gave me said that I had about 7" left on the rear. Does it make sense that they are replacing the rotors and the rear brakes at the same time ? To me if the rear brakes still have 7" left there is no need to replace them. I don't know much about cars but maybe they both have to be replaced at the same time ? Or is the dealer just trying get more $$.