I helped (and by helped I mean I did the work while he watched ) a friend replace his rear brake shoes and wheel cylinders this past weekend. Trouble is, the drums now make a rhythmic scraping sound. I think the drum is touching the dust shield but I am not certain.

We have removed checked to be sure the lug nuts are evenly torqued and this is not the problem. Even with the wheel removed and the drum held in place by hand, it will still scrap.

Ideas?

 

Did you scrape all the rust off the drum and backing plate before re-installing? There could be a small amount still caught in there making the noise. Also all the springs are re-installed and not loose? What I do is put some anti-seize on the backing plate where it makes contact with the other metal parts (backing plate and drum) just to make sure it doesn’t make any noise. My bet would be a little rust causing your noise issues - I’ve had this a couple times.

 

Thanks, we'll give it a shot.

 

If what you are saying is it sounds like something is rubbing somewhere about once every revolution, that is a perfectly normal sound with drum brakes, atleast in my experience. The drum seems to touch the linings on a high spot about once every revolution. This seems to happen even when the drums have been machined. Obviously I haven't heard your noise, but that would be my quess.

 

It does sound like it occurs every revolution. I doubt that it is hitting a high spot, as we backed the slack adjusters off all the way prior to reassembly. Additionally, it is a metal on metal sound and probably louder than steel on semi metallic.

 

Yeah you should hear the shoe slightly rub the drum. I re-read my post and its a little confusing. I mean to put some anti-seize on the three protruding tabs on both sides on the shoe backing plate. Since those will hit the brake backing plate and the drum. But it does just sound like some rust I wouldn’t sweat it.

 

by anychance is the e brake on and if not check the e brake cord it might be putting mild pressure on it and causing a scraping

 

you didnt pry the drum off did you?? something may be bent in one spot

 

Nope. I gave both a wack with a ball pein hammer to jar the drums loose from the oxidation.

We went around the perimeter of the dust cover and bent it back some and it relieved some of the issue. He decided to live with the rest of it.