Project E39 M5: StopTech Front & Rear Trophy Kit Installation

Once we were done with the cut-off wheel we cleaned off the rear brake area with compressed air and some brake parts cleaner.

With our rear dust shield clearanced properly, we can now attach the rear caliper bracket to the OE knuckle’s stock mounting ears. The StopTech aluminum brackets convert the stock ear mounted calipers to stronger and stiffer radial mounts.

Unlike the front rotors, the rear StopTech AeroRotor is much bigger than stock. The StopTech rotor is 32mm thick vs the stock rotor that is only 20mm thick. It is also much larger in diameter measuring in at 345mm vs the stock 327mm. The rotor also has much greater internal vent area to dissipate heat. You can clearly see in this picture where our 4.5 pound weight penalty is coming from.

The rear rotor slid into place without any difficulty or resistance from the e-brake system. Like the front rotors the rear AeroRotors also come with holes necessary to re-install the OE rotor retaining bolts.

Finally we connect the StopTech braided steel brake line for the rear ST40 caliper and the installation of our new StopTech Trophy brake system is nearly complete. Take note that the OE front and rear brake pad wear sensors will need to be safely secured out of the way of any moving parts, as they will not be able to be re-installed into the new StopTech brake pads. You can see our rear sensor dangling to the left of our new rear brake system in the pic above. We simply coiled the wire up and zip tied it to the ABS wiring.