To those who have suffered from squealing brakes . . .
I just recently took my car in for the second time to deal with the squealing brake problem. The squealing was coming from my rear brake on the passenger side.
The first time I took it in, the dealer replaced the passenger-side rear brake pad and commented that the pad they removed was "glazed." This explanation really didn't make any sense to me (how could one pad be glazed after less than 700 miles of normal driving?) but I was just happy that after the installation of the new pad, the squealing was gone.
After about another 700 miles or so, the squealing was back. Again, I heard the squealing emanating from the rear brake on the passenger side. I took the car back to the dealer and the second time around, the tech noticed that the passenger-side rear broke rotor was defective. In fact, BOTH rear rotors were defective (even though there was no squealing associated with the rear brake on the driver's side).
Moral of the story: If you have squealing from your rear brakes, check out your rotors for any surface defects (or have your dealer do it).
'13 Iridium Silver C63 AMG Sedan (540 hp; 500 lb-ft)