2013 Fusion just over 2 yrs old 16,000 mi, took it in due to noise on driver side rear. They tell me my brakes are "caked with salt" and that all 4 brakes need to be replaced. He said that he (meaning Ford) would cover the cost of replacing the front but that I would have to pay for the rear. I live in Florida, drive little and easy. Didn't believe him so I told him I was going to get a second opinion from my old mechanic. He said fine "He'll see, he'll see that they are CAKED with salt" and then added "he'd seen worse but these were really bad ". My old mechanic takes off the wheels and there is nothing, no salt at all. And then I noticed on the "works package" oil change report that the mechanic marked that my front pads are at 7 mm. Would there be any reason to replace those, and what kind of mileage are others getting?