Every once in a while, I have been getting this extremely loud distorting noise from my rear brakes when coming to a stop. I had the pads replaced three weeks ago to pass MD inspection and the front pads are in good shape. It almost sounds the a noise you would hear out of speakers but clearly coming from my brakes...like a loud huummmm. My rotors are definitely due for replacement but I'm wondering if this could be a caliper issue or possibly loose assembly when they reinstalled my brakes after replacing the pads? Only one way to find out but just curious if anyone knows beforehand what this could be. It doesn't happen all the time; maybe once a trip down the road.

 

You shouldn't have to remove the caliper to change rear pads. Mine do the same thing. The lateral run out of the rotor it will cause that noise. So will poor quality pads.

 

Poor quality pads, rotor runout, hot spotted rotors, grooved rotors, and them not installing the anti-squeal shims (which most cheap pads dont come with) will all cause these things.

 

My ABS light tends to come on while driving and then this VERY LOUD vibrating sound comes from the rear sometimes when I brake. When it happens and I let off of the brake and re-apply pressure the sound continues..an EXTREMELY LOUD sound like Ive never heard on any other car before. I believe my ABS system is the culprit in this situation. Can I run the car with the ABS disengaged? Very annoying noise....

 

You need to put the half shims on the rear. Trust me. They are dirt cheap and a piece of cake to put them on and will take care of the noise. I have only had to use them on one of my 850's for some reson, but I had to have them and I was using OEM pads and rotors at the time. My two other 850's and my V70 never needed them.