squeeling rear breaks on 2008 GMC Canyon

the dealer said this is common for this truck. my mech. says it is caused by brake dust. he cleaned them and later that same day they were doing the same thing. any suggestions?

by in Las Vegas, NV on September 26, 2010
2 answers
ANSWER by on February 02, 2011
YOU COULD POSS HAVE GLAZED OVER REAR DRUMS OR ROTORS WHICH WOULD CAUSE THIS TYPE OF PROBLEM THANX FOR THE QUESTION LEE 702-629-2273
ANSWER by on May 23, 2011
First, I have the same squeal in my rear brakes. Yes it is brake dust causing it. But it is only heard on certain braking conditions or after the vehicle has slowed down to almost a stop (with your foot still loading the brake pedal firm). Now I haven't done this as yet, but will be soon enough. I will soon be replacing my brake shoes and pads. I found out that you can purchase ceramic shoes for the rear brakes - which I will be doing. Your truck has ceramic front pads and semi metalic rear shoes.(from the factory) Ceramic pads do not heat up and also do not shed brake dust particles like the asbestos or semi metalic ones do. I don't think you can purchase asbestos brake shoe now, or can you? Anyways, I never use those ones.