The Stovebolt Site Forums The Shop Area Driveline Squealing brakes, again and again?

So ya ever have a big old garbage truck pull up next to you at a stop light and hear it
coming long before you ever see it by it’s squeallllllll???
Well taint only big old trucks that are plagued by it. I’ve had the embarrassment of
squealing brakes with me on and off for years.
Now before you go and look up all the symptoms on the internet for to respond with a
diagnose, let me say, that I’ve been doing brake jobs on my own and other cars
since I was a pre-driver teen. Pop was an old school mechanic and taught me brake
work before I ever had my own cars, and I’m now 73 years into it.
This is the first one that I’ve had this severe of a problem with brake squeal. Let’s get
clear that there is a difference between brake squeak and brake squeal. Brake squeak
is what you hear when you’re sitting still in the drive way you hear a squeak when you
apply the brake as all the dry metal parts expand out to meet the drum or disc.
Brake squeal is the steady screeching you hear when rolling to a stop.
Number one cause is usually glazed lining and is easily remedied by sanding the shoe
with some 80 grit to remove the dust that is been packed into the surface of the lining. I
also rough up the drum and check that they have no hot spots or high spots and that
they are wearing evenly.

So….the lining that I used on my ‘50, 3600 Huck brakes, which I believe came from one
of our old truck vendors, seem to glaze up after a few weeks driving, which translates
into six or eight hundred miles.
The drums are round, (indicated them), they are in good condition, they were turned
about .020” when I did the brake job, turned them myself and they do not pulsate when
applied. They are not distorted and the backing plates are not bent either, the brake
shoe return springs are not weak or broken and the front wheel bearings are in good
shape and are properly adjusted.
The linings are dry, not saturated, nor do they have any signs of contamination.
Once they begin to glaze up they squeal cold or hot equally well.
When I pull the drums to de-glaze them, there is not an excessive amount of dust, in
fact there is very little dust, which suggests to me that the lining may be too hard of a
compound.
With about 15K on this brake job, there is still over ¼” of lining left and there wasn’t
much more than that when it was new.
The leading edge of all the shoes, I’ve chamfered back about ¼ to 5/16”.
The squealing develops at about the same time on both the front brakes after servicing
them.
The rears have not given me any problem, I suspect that they may be a different
compound, quite possibly from a different supplier.

So what do you old experienced mechanics think, maybe just as simple as too hard of a
compound???

Denny Graham
Sandwich, IL

Yep, you nailed it. All brakes make noise- - - -hard linings make a lot more noise, which is a tradeoff for long lining life. Either go to a softer lining material that makes a lot of dust, wears fast, and doesn't squeal as much, or turn off the hearing aid. Since I quit hearing frequencies in the brake squeal range about 25 years ago it isn't an issue for me. Too many jet engines, race cars, and deer rifles, and not enough hearing protection. Of course, the ringing noise in my ears that I hear 24/7 can be a bit distracting!
Jerry

I have often wondered if the paper gasket that they used to put between the hub and the drum helps this situation. Also, didn't they use a spring around the drum years later to combat squeal?

Do believe your right Fred. Chevy's used to have the springs on
their front drums, don't recall them on the rears though but my
memory isn't what it used to be 50 or 60 years ago.
I've used a rubber strap while turning drums when I worked at the
auto parts back in the 60's, that to dampen the ringing while
turning them.
Think I'm gonna do some searching for some softer shoes, these
might last 60K but I can't take the screeching and it's really
embarrassing at a car show or cruse night when they squeal at
every touch. And I can't afford the time to pull the drums and
sand the shoes every two or three weeks. So if I get 30k out of
a set of shoes with softer compound, that's a good five or six
years, maybe more if it keeps on raining like it has been.

Me and the mutt, took old blue out to run some chores this
morning and put about 40 miles on her. Brakes were just as quiet
as they could be for the first 30 miles or so, then
they started to sing to us at every stop as we
headed for home.
dg

Denny, the springs around the drums may do the trick for you. Back when I worked at the Chevy dealership in the after school programs (65/66) the springs were a cure for many brake squeals even that late in the century....and it was always the front.

....I just finished the brakes on the 50 coupe and the springs were on the front but not on the back which I THINK is the way they came from the factory. I remember on ONE occasion buying and using the spring for the front door of a house and it worked to stop the brake squeal.

Other theories/guesses:
- http://forums.aaca.org/topic/71957-purpose-of-spring-around-front-brake-drum/
- http://www.chevytalk.org/fusionbb/showtopic.php?tid/272775/

Consensus seems to be to minimize chatter/squeal/vibration - anti-vibration, anti-"harmonics".

I get my linings from these guys. They have the "softer" linings and they work great. They know and understand old stuff.

www.brakeandequipment.com

But they only list years back to '62 Don, just like many of
the big box auto parts outlets.
Problem with them is that they have inexperienced kids working
the counter who only know how to read what's on the computer
screen, which, we can do also.
I haven't seen a vendor that lists soft/medium/hard as a choice.

As far as installing a damper on the drum, I would try them if
I could find the correct size spring. There are three grooves
that could retain a spring damper. I'd be willing to try that
before replacing the shoes because the brakes are great on
this truck except for the squealing.
http://www.pbase.com/dennygraham/image/140334438

But, I have to say, I'd only give a damper spring about a
10% confidence score, I'd bet a different compounded lining
will end up being the answer.

I kind of expected to hear some similar stories from people
that have used shoes from our online vendors. Surely I'm not
the only Advance Design operator that is experiencing this
annoyance, I'm sure others have used lining from our
old truck vendors, no?
dg

Denny,

I have not used linings from any of the reproduction vendors as they don't make much for the larger trucks. I did; however, find a local old school brake/clutch vendor in my area that installed friction material to my shoe cores. He recommended a "high friction" compound that would have been used on old vehicles like our antiques. I don't have the diving miles behind me to say if they squeak or not, but so far they have been great. The best part of the whole deal is that brake/clutch guy did the job for a very reasonable price, perhaps better than the reproduction vendors.

Paul

Denny, you need to call them and ask for the shop. The guys in there do the specialty lining, arching shoes and other special services. Sorry I should have mentioned that.

I figured as much Don, since they specialized in brake work.
A little far away for me. Got a local re-builder down near
Midway airport in the city.

Paul, the first thing I did when I brought my '50, 3600 home
was a complete brake job, easiest source at the time was JC
or Chevy Duty or one of my other top four, can't recall which
one it was. Those are the lining that I've been running for
the past 15K.
When I rebuilt the motor and trans, I took my disc and
pressure plate into the city to a shop that specialize in
clutch and brake rebuilding for commercial trucks. They did
a bang up job using on the disk using VelveTouch facing.
http://www.pbase.com/dennygraham/image/128167927
Gonna try and find damper springs that would fit these drums
first. Then I think I'll pull the shoes and have them bond
some suitable lining to my cores. Gonna ask them if they can
arc the new lining to match the drums.
Got a plan, and I'm gonna get the old gal to quit her
screeching yet this summer.

dg

Denny, the plain old screen door spring from a hardware store should be sufficient to do a test run, even if you have to splice in a short extension to match the circumference of the drum. Any sort of damper around the drum that will interrupt the harmonics should be sufficient to minimize the squeal, and if it works, maybe you can source a piece of bulk spring and make one that's exactly the right length. One item that comes to mind would be a piece of a spring-type drain cleaner snake, cut to the right length to wrap around the drum with a little stretch to keep it in place.
Jerry

You're thinkin' is right up my alley Jerry. Searched for a
couple of hours last night and another this morning for damper
springs and the only one that I came up with, were a $50 pair
for a Mopar.
Thought of the screen door springs also even though they are
no where near the tension of the original damper springs but
you're right, any thing to upset the harmonics should work,
just to prove the point. Even thought I might attach a piece
of heavy rubber with two opposite tension springs to balance
out the weight of the springs.
Got painting to do this afternoon and it's raining today and
most of next week, so I probably won't get a chance to try
anything till next week.
dg

I hope you can tolerate the smell of burning rubber- - - -that brake drum is basically a heat transfer device and a stop from highway speed transfers enough heat to melt an average-sized cast iron skillet. A couple of short, heavy bungee cords would act as a damper, but they would only be good for a few stops at low speed.
Jerry

I understand Jerry, converting motion to heat, basic physics right?
But I'm pretty gentle on the brakes Jerry, mostly use the
down shift to slow the pony down, unless I have to make a
panic stop. And I'm almost all my driving is under 45. Have to
get out my Laser thermometer and check that out next time I
make a series of stops, just so I can gather some data to work
with. I'm not much of a believer in faith alone.

Thought about a couple of bungees but thought they would be
to bulky to stuff back in there.


dg

Denny, What diameter drums do 3600's use? Are they 11" or 12"?
I am sure I could come up with original springs for 11" drums if that would help.

Thanks for jumping in here Dave. They are 11" on the 3600, went
to 12" on the 3800.
http://www.pbase.com/dennygraham/image/160723376

I'd sure appreciate it if you could come up with a pair. They so
rarely need to be replaced that no one stocks them. By the time
a damper spring is rusted out the drums need to be replaced.

Denny Graham
Sandwich, IL

Are they 11" on the 3100?

I'll look at my old drums (in deep storage), if they are 11". If they are right for you, and if I can get them off so they are useable, I'll give/trade them to you, Denny.

I don't have a 3100 here to check them Tim but I do believe
they were also 11" front and rear.
The rears on the 3600 are 12".

dg

3100's are 11" all the way around.

I will try to remember to check to see if I have a couple of drums with those springs. PM me tomorrow evening to remind me (I am now passing a kidney stone and will not remember much of what happens tonight).

Just for info,
My 3804 has 12" on the front and 14" on the rear.
steve sr.

Missed those earlier, went there, got them, tks Dave.
I'll give those a try. Hope they're not just back door springs
that the ebay vendor is passing off as the real brake drum
damper springs, which are much heavier than screen door
springs. Zip Products Inc. is a large Corvette parts supplier,
so I should be alright.
But....those dampers are gonna cost me dang near as much as
having a softer lining bonded to my old Huck brake shoe cores.
Anyway, it's worth a try to see if they would help or possibly
eliminate the squeal. I put a rubber band around my wine
class last night and couldn't get it to ring when I rubbed
my dampened finger around the rim.

And one more time.......I'm the only one driving an Advance
Design Chevrolet truck that is having a noisy brake problem,
right??????
Or are the rest of you that have gone thru this to proud to
admit that you're suffering from the same plague?
http://www.pbase.com/dennygraham/huck_brake_service
dg

Maybe its your ears. I'm sitting on my couch, 900 miles from your house and I hear what sounds like it could be your brakes squealing.
Carl

Denny, running stock drums/brakes on the front and rear of my 52 panel and no brake squeal......yet and I've had to heat them up, and make a few "quick" stops. My luck may run out though.

I've got a '47 F**d that I drive a good amount this time of year and the brakes did the squeal and I had the shoes arched last fall and have not had the dreaded noise since....