Brake Squeal at 35mph gets louder as I slow down

[elhajj33]

I'll be the first to say this is odd. I have 2009 Fleetwood Excursion DP with about 20K miles on it.

I have air drum brakes that have been getting progressively louder over the last few months. The coach brakes perfectly fine - no issues there. But, starting at 35mph the brakes start to squeal. The squeal gets louder as I come to a stop. It's not a mildly annoying whine, it's a loud squeak.

The coach is on a freightliner xcm power bridge chassis and I can't believe it needs brakes at only 20,000 miles (even though we've been up and down mountains quite a bit).

I have tried turning the wheels and spraying the brakes. That seems to work, but only for about an hour or so. After that: squeal is back.

Any thoughts?

[elhajj33]

DSDP Don wrote:
Those drums and shoes are over 3" wide, you just won't get back in there far enough. You really don't want to do an uneven job either.

Ah, true true. Thanks again for the advice. I'll let you know how operation "Days of Thunder" goes. 🙂

[DSDP_Don]

Those drums and shoes are over 3" wide, you just won't get back in there far enough. You really don't want to do an uneven job either.

[elhajj33]

DSDP Don wrote:
You won't successfully be able to get inside the drums (from the outside) .

Will definitely warn the fam! They'll probably enjoy it 🙂 as for the drums: I can see the brake shoes and the drum itself from behind the wheel (did you see the pics I posted?)

Can't i sand a little in there? Let me know what you think. Slamming on the brakes would still be fun anyway 😉

[DSDP_Don]

You won't successfully be able to get inside the drums (from the outside) and sand them. Try a few hard stops to see if you can eliminate some of that glazing. On this next trip, warn the family and do some occasional hard braking when doing things like exiting an off ramp.

[elhajj33]

DSDP Don wrote:
Question? Do you routinely use your exhasut brake, even in town/traffic. .

Hey Don, thanks for the advice. I only use the air brakes on steep grades (of which the are plenty here in California. i never use them for regular driving.

I do, however, try to feather the brakes when i'm rolling down a hill. I wonder if i managed to glaze them or the drum wall?

I can reach the inside of the drum as you saw from the pics. I could try sanding the drum wall a bit?

I can also try some brake clean (what do you think?)

We roll again in a few days, i can try a few hard brakes then

[Cobra21]

DSDP Don wrote:
Hold on guys, first, most of you are talking about car brakes, not air drum brakes, which the OP has. Per his pictures, you can see that a drum brake on a diesel pusher is open in the back and has no backing plate.

Question? Do you routinely use your exhasut brake, even in town/traffic. If you do, it can glaze your brake shoes. This happens because you're infrequently using the brake pedal and the drums lightly skim over the linings, essentially polishing them. After awhile they glaze over and will squeal.

Take the coach out by yourself, find a quiet road, run the coach up to about 45-50mph and STAND on the brakes. Do this 2-3 times. You may find that the squeal goes away or is substantially reduced. The other option is to pull the drums, turn them and do a qick sand on the linings to rough them up.

If you are using the exhaust brake excessively, quit doing so. It should be used on grades and hard stops, but not for everyday stopping in traffic or around town. Guys are so worried about saving their brake linings, they over use the exhaust/engine brake.

Sorry, my bad; Don has it here!

[DSDP_Don]

Hold on guys, first, most of you are talking about car brakes, not air drum brakes, which the OP has. Per his pictures, you can see that a drum brake on a diesel pusher is open in the back and has no backing plate.

Question? Do you routinely use your exhasut brake, even in town/traffic. If you do, it can glaze your brake shoes. This happens because you're infrequently using the brake pedal and the drums lightly skim over the linings, essentially polishing them. After awhile they glaze over and will squeal.

Take the coach out by yourself, find a quiet road, run the coach up to about 45-50mph and STAND on the brakes. Do this 2-3 times. You may find that the squeal goes away or is substantially reduced. The other option is to pull the drums, turn them and do a qick sand on the linings to rough them up.

If you are using the exhaust brake excessively, quit doing so. It should be used on grades and hard stops, but not for everyday stopping in traffic or around town. Guys are so worried about saving their brake linings, they over use the exhaust/engine brake.

[elhajj33]

11178adm wrote:
a high percentage of over the road trucks have the rear axle brake covers removed to prevent dust accumulation

Looks like the backing is off here too. Take a look at the images at this link. The shoes look thick, but I could be wrong.

Link with Images

[Tyler0215]

ANY brake noise needs to be checked out. Brakes don't fail, they gradually get worse till they don't work.

[11178adm]

if you can identify the wheel that the noise is coming from that would be the place to start. if you are willing and able to get under the MH there are two rubber plug on each wheel backing plate, they are about 1 inch long and 3/8 in. wide take them out with a small screw driver and with a flashlight you can see the side of the brake shoes, a new shoe is close to 3/4 in. thick, there should be a line around the side of the shoe at the 1/4 in. thickness, that is how DOT checks them on trucks. anything less than 1/4 in the rivets that hold the lining to the shoe will be wearing into the drum and the bakes and drum are not safe to operate. with a lot of mountain driving also it is possible that the shoes are cracked sometimes that is visible through the inspection holes. if the shoes are good and no cracks it could be a accumulation of brake dust in the drum causing the noise. a high percentage of over the road trucks have the rear axle brake covers removed to prevent dust accumulation

[Cobra21]

There is a small metal clip on the pads that comes in contact with the rotor before the pads are gone. This tells you to go get new pads on before you take your rotors out. Pretty sure this is what you are hearing.
Brian

[elhajj33]

sounds like a trip to the mechanic is in order. I've replaced pads and rotors on a van, but those wheels don't weigh five-million lbs.

There goes a grand ugh...

[rgatijnet1]

You may have an obstruction in a rubber flex line or a dented steel brake line that is not allowing your brake shoes to fully retract.

[donn0128]

Metal on metal. Your brakes are either worn out, (best guess) or rusted drums from non use.