Rubbing/grinding noise on new drum brakes

[Mike W.]

I have an odd problem with the brakes I replaced. I replaced the
drums and shoes on a 2001 Cavalier. When I replaced the shoes, I also
used new hardware/springs.

It seems like things are working well, but when you are stopping,
there is a rubbing/grinding noise that is heard from them. This
happens at about 30 mph's until you come to a complete stop. I've
taken them apart, and I can see some wear in the shoes, so I know that
it's somewhat working. When I take the shoes all the way off, it
looks like it might be grinding/rubbing against the back plate. When
I put everything back on, it's quiet for a few days but then goes back
to the rubbing/grinding noise.

I used Pennzoil "Premium Wheel Bearing Grease" (707L). It says on the
package that it's OK to use on brakes, and figured it was good. I
placed this all over the back plate, the spindle thing on the bottom,
and wherever it might look like there's some contact. This doesn't
seem like it did the trick though.

Thanks in advanced for any solutions!!

[Hobo]

Post by Mike W.
I have an odd problem with the brakes I replaced. I replaced the
drums and shoes on a 2001 Cavalier. When I replaced the shoes, I also
used new hardware/springs.
It seems like things are working well, but when you are stopping,
there is a rubbing/grinding noise that is heard from them. This
happens at about 30 mph's until you come to a complete stop. I've
taken them apart, and I can see some wear in the shoes, so I know that
it's somewhat working. When I take the shoes all the way off, it
looks like it might be grinding/rubbing against the back plate. When
I put everything back on, it's quiet for a few days but then goes back
to the rubbing/grinding noise.
I used Pennzoil "Premium Wheel Bearing Grease" (707L). It says on the
package that it's OK to use on brakes, and figured it was good. I
placed this all over the back plate, the spindle thing on the bottom,
and wherever it might look like there's some contact. This doesn't
seem like it did the trick though.
Thanks in advanced for any solutions!!

Did you have the shoes arced to the diameter of the drums? If not you're
only getting partial contact which may be causing the shoes to chatter
against the drums.

[Mike W.]

Post by Hobo
Did you have the shoes arced to the diameter of the drums? If not you're
only getting partial contact which may be causing the shoes to chatter
against the drums.

Thanks for the response. I did not do that. That could very well be
what the problem is. I've never changed the drum brakes before, so I
really don't know how to 'arce' the shoes. Does this just mean adjust
the spindle adjuster thing so that the drums require a little more
effort getting back on?


Thanks!

[Hobo]

Post by Mike W.

Post by Hobo
Did you have the shoes arced to the diameter of the drums? If not you're
only getting partial contact which may be causing the shoes to chatter
against the drums.

Thanks for the response. I did not do that. That could very well be
what the problem is. I've never changed the drum brakes before, so I
really don't know how to 'arce' the shoes. Does this just mean adjust
the spindle adjuster thing so that the drums require a little more
effort getting back on?
Thanks!

No, not that simple. What you need to do is take the drums and shoes to
a brake shop to have it done. What happens is they measure the inside
diameter of the drums with a micrometer type gauge to get an accurate
reading for each drum. Depending upon the results, and the condition of
the drums, they may need grinding to get rid of score lines or any
out-of-roundness. They can only grind them a certain amount before they
are too thin for safe use and need replacing. Anyway, after that they
place the shoes for each drum on an arc grinder, the grinding arc of
which is set to match each drum's exact diameter. When done properly the
surface of the shoe will fit completely flush against the inside of the
drum.

When placed back on the car, and the brakes are activated, you'll get
full braking resistance due to the entire surface of the shoe making
contact.

[Mike W.]

Post by Hobo

Post by Hobo
Did you have the shoes arced to the diameter of the drums? If not you're
only getting partial contact which may be causing the shoes to chatter
against the drums.

Thanks for the response.  I did not do that.  That could very well be
what the problem is.  I've never changed the drum brakes before, so I
really don't know how to 'arce' the shoes.  Does this just mean adjust
the spindle adjuster thing so that the drums require a little more
effort getting back on?
Thanks!

No, not that simple. What you need to do is take the drums and shoes to
a brake shop to have it done. What happens is they measure the inside
diameter of the drums with a micrometer type gauge to get an accurate
reading for each drum. Depending upon the results, and the condition of
the drums, they may need grinding to get rid of score lines or any
out-of-roundness. They can only grind them a certain amount before they
are too thin for safe use and need replacing. Anyway, after that they
place the shoes for each drum on an arc grinder, the grinding arc of
which is set to match each drum's exact diameter. When done properly the
surface of the shoe will fit completely flush against the inside of the
drum.
When placed back on the car, and the brakes are activated, you'll get
full braking resistance due to the entire surface of the shoe making
contact.

What a pain! Is this a common thing to do when you replace drums and
shoes? After you mentioned it, I did google it and it looks like it
was a practice from awhile ago. If I just let it go for awhile
longer, will it eventually arc itself? They don't tell you that in
Chilton's! :)


Thanks for the information!

[Vic Smith]

Post by Mike W.
What a pain! Is this a common thing to do when you replace drums and
shoes? After you mentioned it, I did google it and it looks like it
was a practice from awhile ago. If I just let it go for awhile
longer, will it eventually arc itself? They don't tell you that in
Chilton's! :)

I never had "arcing" done.
Never even heard of it.
And never had shoes that didn't wear pretty evenly unless they weren't
adjusted.
Make sure your self-adjusters are working properly.
Double-check that you're using the right shoes.
If the noise is from one side only see if you can find the difference.
You said the shoes "might be" hitting the backing plate.
Might take the shoes to a different parts store than where you bought
them, or to a GM store, and compare them to what they say are the
right shoes.
With new drums and shoes, this just shouldn't happen unless a part is
wrong or you didn't attach something right.

--Vic

[HLS]

Post by Hobo

Post by Hobo
Did you have the shoes arced to the diameter of the drums? If not you're
only getting partial contact which may be causing the shoes to chatter
against the drums.

Thanks for the response. I did not do that. That could very well be
what the problem is. I've never changed the drum brakes before, so I
really don't know how to 'arce' the shoes. Does this just mean adjust
the spindle adjuster thing so that the drums require a little more
effort getting back on?
Thanks!

No, not that simple. What you need to do is take the drums and shoes to
a brake shop to have it done. What happens is they measure the inside
diameter of the drums with a micrometer type gauge to get an accurate
reading for each drum. Depending upon the results, and the condition of
the drums, they may need grinding to get rid of score lines or any
out-of-roundness. They can only grind them a certain amount before they
are too thin for safe use and need replacing. Anyway, after that they
place the shoes for each drum on an arc grinder, the grinding arc of
which is set to match each drum's exact diameter. When done properly the
surface of the shoe will fit completely flush against the inside of the
drum.
When placed back on the car, and the brakes are activated, you'll get
full braking resistance due to the entire surface of the shoe making
contact.

What a pain! Is this a common thing to do when you replace drums and
shoes?

I have had it done when I bought shoes at a shop that offered to do it
for free, but I have also fitted many sets of shoes that were not fitted.

Unless something is really out of shape with the drums, or the shoes are
of poor quality, they will seat in soon enough. There is a procedure for
seating a new set of shoes by pulling forward, applying the brakes,
backing up and applying the brakes, etc. This also will bring the
automatic adjusters to their proper adjustment.. You did pre-adjust
those brakes, didnt you?

[Mike W.]

Post by HLS
automatic adjusters to their proper adjustment.. You did pre-adjust
those brakes, didnt you?

When you say pre-adjust, do you mean move the spindle out a touch so
that the drum fits snugly on? I did, but I'm wondering if I didn't do
it enough.

I have some extra time this weekend, so maybe I'll try to go forward,
reverse, parking brake, etc and see if it adjusts. Also, I still have
the old shoes so maybe I'll try to measure them up and see if they are
the same size.


thanks,
mike

[hls]

Post by HLS
automatic adjusters to their proper adjustment.. You did pre-adjust
those brakes, didnt you?

When you say pre-adjust, do you mean move the spindle out a touch so
that the drum fits snugly on? I did, but I'm wondering if I didn't do
it enough.

I have some extra time this weekend, so maybe I'll try to go forward,
reverse, parking brake, etc and see if it adjusts. Also, I still have
the old shoes so maybe I'll try to measure them up and see if they are
the same size.


thanks,
mike

***********
Rear drums have some provision for preadjustment, which will get the shoes
near
enough to the drum surface so that the automatic adjusters will take over.
You normally put the drum back over the shoes and assembly, and snug it
down (by lug nuts or screws or whatever system). Then you go in through
the backing plate and adjust the star wheel until the shoes touch, but do
not
bind the drum. (Your rear drum assembly could vary somewhat).

After this, as you back up and apply the brakes, the starwheels will advance
if necessary to keep the rear shoes adjusted properly.

These starwheel adjusters have to be clean and freely movable before you
reinstall them.

If you havent done this kind of job very much, let me also caution you that
the adjuster mechanisms are side specific. You cannot put a left wheel
adjuster
on a right wheel and expect it to work.

There are many variants of rear disc brakes, and some variations of rear
drums.
The drums are usually dead simple; some of the disc systems are not.

[joejoegun]

Post by Hobo

Post by Mike W.

Post by Hobo
Did you have the shoes arced to the diameter of the drums? If not you're
only getting partial contact which may be causing the shoes to chatter
against the drums.

Thanks for the response. I did not do that. That could very well be
what the problem is. I've never changed the drum brakes before, so I
really don't know how to 'arce' the shoes. Does this just mean adjust
the spindle adjuster thing so that the drums require a little more
effort getting back on?
Thanks!

No, not that simple. What you need to do is take the drums and shoes to
a brake shop to have it done. What happens is they measure the inside
diameter of the drums with a micrometer type gauge to get an accurate
reading for each drum. Depending upon the results, and the condition of
the drums, they may need grinding to get rid of score lines or any
out-of-roundness. They can only grind them a certain amount before they
are too thin for safe use and need replacing. Anyway, after that they
place the shoes for each drum on an arc grinder, the grinding arc of
which is set to match each drum's exact diameter. When done properly the
surface of the shoe will fit completely flush against the inside of the
drum.
When placed back on the car, and the brakes are activated, you'll get
full braking resistance due to the entire surface of the shoe making
contact.

Actually and I know this is an old post the problem he is having is poor manufacturing processes. Quality Shoes and Drums should fit and his apparently don't. This is 2017 and not much has changed in fact it's gotten worse: the CEO needs another car to complement the 40 he/she already has or another house to add to the 7-10 they already have etc etc etc. The junk that is being sold today is much worse than what was sold in 2009 but it all began in the parts industry back in the late 70's to early 80's as in Sold by Dana or Delco or whatever major brand doesn't mean it was made by them just requisitioned by them to be made.

[Anyolmouse]

Post by Hobo
Did you have the shoes arced to the diameter of the drums? If not you're
only getting partial contact which may be causing the shoes to chatter
against the drums.

Thanks for the response. I did not do that. That could very well be
what the problem is. I've never changed the drum brakes before, so I
really don't know how to 'acre's the shoes. Does this just mean adjust
the spindle adjuster thing so that the drums require a little more
effort getting back on?


Thanks!

If you bought new drums and shoes they should be of the right diameter.
When drums are turned the circumference will be slightly larger than
than the shoes.

[Anyolmouse]

"Mike W." <***@gmail.com> wrote in message news:01203614-d820-43ec-8627-***@g23g2000vbr.googlegroups.com...
| I have an odd problem with the brakes I replaced. I replaced the
| drums and shoes on a 2001 Cavalier. When I replaced the shoes, I also
| used new hardware/springs.
|
| It seems like things are working well, but when you are stopping,
| there is a rubbing/grinding noise that is heard from them. This
| happens at about 30 mph's until you come to a complete stop. I've
| taken them apart, and I can see some wear in the shoes, so I know that
| it's somewhat working. When I take the shoes all the way off, it
| looks like it might be grinding/rubbing against the back plate. When
| I put everything back on, it's quiet for a few days but then goes back
| to the rubbing/grinding noise.
|
| I used Pennzoil "Premium Wheel Bearing Grease" (707L). It says on the
| package that it's OK to use on brakes, and figured it was good. I
| placed this all over the back plate, the spindle thing on the bottom,
| and wherever it might look like there's some contact. This doesn't
| seem like it did the trick though.
|
| Thanks in advanced for any solutions!!
|

Same symptoms on a GM Safari after the last brake job. I noticed a lot
of brake shoe dust trapped in the rear drums. Cleaned out the dust and
no noise for awhile. When I asked the parts house about it, the guy said
that it is pretty much normal with the materials used in brake shoe
material now days. I have decided to wait until they are worn out and
then try OEM parts from the dealer and see how that goes. The brakes
work fine-- they just sound like metal to metal when there is plenty of
shoe left.