My wife's 330i needs new rear brake pads. I measured them with the special BMW tool and they are slightly above 3 mm. She has 112K miles on the car and had gotten new rotors and pads at 50k miles from the dealer. I measured the rear rotors and they are at 20.73 mm thickness. I remember seeing somewhere on this site that the recommended minimum thickness for rear rotors was 20.4 mm. So if I get the same OEM pads (Textar), is it safe to assume that the rotors will last for these second set of pads? Also, at what point does one need to consider replacing the parking brake shoes?