I just changed my rear brakes for my Mercedes-Benz S500, it was one of the easiest brake changes I have ever done. Here is what I did...
1. Jack up the car and remove one of the rear wheels. It is ok for the hand brake to be engaged because I am not going to remove my rotors.
2. Immediately you will see a large pin, about 5 mm in diameter, punch it out using a torx screw driver + hammer. I found this to work the best, you can use punch pins too but I left them in my other house. The front brakes needs two 1/8" pins, the rear brakes uses a single much larger pin.
3. Remove the brake sensor, in the rear there is only one sensor for both sides. The front brakes has two sensors for both front wheels.
3. Once pin is removed, the flat brake spring will come out, please remember how it is positioned as you must put it back in the same way.
4. Use a flat head and wiggle the brakes until they are loose, than use your hex screw driver and pry them out. There should be little resistance.
5. You will need a brake pad spreader that can spread the pistons back. The caliper i used looks something like this...
We are changing the brake pads without removing the caliper, thats why you need this kind of tool.
6. When finished, double check to make sure you have the right matching brake pads, transfer the metal shims over to the new pads. I added some paste on the old shims so they will be more quiet.
7. Do everything in reverse, using the torx screw driver to hammer the pin back into position. Make sure the pin is hammered until it no longer can move.
8. Re-install a NEW sensor, never re-use the old one as the plastic trip is broken thats why you get the annoying "brake lining low, visit workshop" error message. The sensors only fit one way, so its pretty straight forward.
9. Re-install the wheel using a 14mm wheel hanger similar to below...
WheelHanger.com - The Ultimate Wheel Hanger
10. Press the brakes like ten times, to re-adjust the new pads.
The instructions seem long but all this took me only 20 mins to do each side. Any questions, please let me know! I saved myself $150 from the stealership!