E36 BMW Rear Brake and Emergency Brake Problems
|I last replaced the rear brake pads and rotors on my 1995 BMW 325is back in early 2003. I've since put 100k on the car and figured that it might be time to do this job again. Of course, front brakes don't last nearly as long...but that is because that's where the majority of the braking energy/force comes from. Recently, a metallic rattling noise had been coming from the back of the car somewhere. Given E36 BMW models' propensity for worn subframe, rear trailing arm and other bushings, I thought it might be best for some process of eliminating type preventative maintenance. After jacking up the car and removing the rear wheel, I removed the 2 15mm caliper bracket bolts and slid the brake caliper off of the car. I was shocked to see that the brake pads appeared to be only about half worn! The rotor itself looked a little worn, but was still smooth and straight. I confess to not measuring the thickness to see if it was within spec. Besides, I was already in there...might as well do the job anyway.|
E36 BMWs can be maintained relatively inexpensively by experienced do-it-yourself/shade tree mechanics, especially if you know where to look for deals on parts. I bought ATE oem replacement rear brake rotors and PBR metalmaster rear brake pads on ebay for about $100 total. Using an allen wrench, I removed the rotor locating screw, and pulled on the rotor, which remained steadfastly stuck in place. Figuring corrosion to be the culprit, I tapped the rotor on each side with a rubber mallet. One side came free, the other side refused to move, like something was holding it on there. Out came a real mallet - old rotor be damned! It STILL wouldn't come free. Turns out that the locating pins for the emergency brake assembly had both pulled their mounts on the brake dust shield backing plate, also referred to as the brake protection plate. This in turn allowed the e brake shoes to expand outward and move around, holding the rotor in place.
T0 repair this, I'll need a new brake shield plate. According to the realoem BMW digital microfiche, suggested retail is only something like $18.94. I'm sure my local stealership has marked it up 2 or 3 times that, as they have done for many other pieces. For a temporary repair, I simply removed the entire emergency brake assembly from the passenger side of the car. The anchor-like cable ending must be removed as well, or it will rub against the hub and or rotor. Ask me how I know. It simply pushes out using a hammer and punch. I ended up installing the new rotor and leaving the old pads on for the time being. A week or two like this won't hurt anything, and the driver's side e brake still works.
Tip: Wire brush dirt and corrosion off all bolts prior to re-assembly and lightly coat threads and mating surfaces with some kind of anti-seize compound such as Permatex Never Seize. I also put a little of this on the hub and the front of the rotor. Some people use white lithium grease. I cannot comment on this.
PS: While the broken and floating e-brake assembly was indeed rattling around, removing it failed to cure the rear end rattles audible over bumps. I'm puzzled.