When the car is almost stopped, one or both of the rear drum brakes makes a sound. I'll call it a hum. It definitely isn't a scraping, scratching or screeching sound. Anyone else solved this problem? I took the wheel and drum off of one of them and cleaned it. Thought it was gone for awhile but then it came back. Any help would be appreciated.
My guess would be that you are hearing the brake shoes vibrating. If at your inspection and cleaning there wasn't any sign of leaking, the drums were smooth and the shoes were not worn excessively, I don't think you have a problem.
There's typically 3 contact points between back of brake shoe and the backing plate. I'm not familiar with Prius drum brakes, but usually if you remove the brake shoe hold down clips, you can pull the shoes away from the backing plate enough to put a dab of high temp grease on the contact points. Be careful to not get it on the shoe itself. Might help, worth doing periodically anyway.
Are they adjusted correctly? The shoes should just kiss the drum. Check both sides. Is the parking brake working right? Are all shoes evenly worn both sides? How much pad left? Check wheel bearings and struts and suspension bushings while you're back there.
thanks, I lubricated as you suggested, as best I could, and got rid of the hum. I appreciate your time and advice.
