It is now time to move on to the back of our M5. Just like the fronts, we start by removing the OE caliper and mounting bracket. The rear rotors also have a couple of small retaining bolts that must be removed.
Next the rotor is loosened with a few taps of a soft hammer to facilitate removal. Be sure your e-brake is off before trying to slide the rear rotor off. Depending on how tight your e-brake is it may take more persuasion than the front to slide the rear rotor off.
With the rotor off, the heat shield must now be trimmed down to make room for the much larger rear Stoptech AeroRotor. This is where things get a little more difficult. The heat shield cannot simply be removed like the front, because it is a part of the parking brake’s backing plate which holds some of the small e-brake components.
The outer part of the dust shield is removed by using a cut off wheel..
You can see here the ridge that must be followed with the cut-off wheel. Take your time when doing this. Too much and you will mess up the area the e-brake components need to function properly, not enough and the new rear caliper mounting bracket and rotor will not fit.
Once the outer part of the dust shield is cut off, we carefully start working down and shaping the dust shield in order to start test fitting both the rotor and brackets. It took us a few tries to get it perfect, but this process is necessary. If a perfect fit is not achieved the caliper bracket will not allow the caliper to sit exactly where it was designed to and/or you can have noises from the high edges of the dust shield rubbing on the back of the rotor.