Identify this noise - Tilted Forum Project Discussion Community

scoobydugan · 08-22-2003, 01:49 PM

Hey guys....went to change the rear brakes....I swear I heard the trademark squeeling of the brake wear sensors....turns out that i have a little under a 1/4" of pad left....not the brakes....any idea what the noise could be?

Kurant · 08-22-2003, 01:55 PM

If it's just the squeeling noise from the brakes it could be a flaw in the material in the pad or rotor, or 100 other things...

My M3 has had squeeky brakes in one pad from the day I bought it. BMW said nothing was wrong internally, and they changed the pads and it stopped. It was a brand new car.

Squeeking doesn't always mean somthing bad is going on, brakes can just squeek from flawed materials. If that's the case, it'll stop. But changing it still is never a bad idea.

otter · 08-22-2003, 02:03 PM

Dirty drums can cause squeeling. Grab some brake cleaner and clean the inside of the drums, see what that does.

scoobydugan · 08-22-2003, 02:10 PM

Yeah, otter i already tried that....I'm selling the car so I would rather not put any money into it...but its only $15 for new pads....i could always explain the noise to potential buyers...anyone wanna buy a 91 chevy beretta GT?

FastShark85 · 08-22-2003, 04:17 PM

Take a high-pressure hose and wash the rotors and pads thoroughly. It does the trick for me for the first few hundred miles. Brake dust builds up and can cause squeaking.

Your brake dampers may also be worn out, given the small amount of pad left.

scoobydugan · 08-22-2003, 08:06 PM

its not a small amount of pad, thats the thing, it's kind of odd actually....it almost looks like theyre brand new...I tried cleaning with a high powered hose, and i took an air chuck to clean them off...with a mask on of course

grumpyolddude · 08-22-2003, 08:19 PM

You might try getting the rotors resurfaced, or take some emery cloth and knock th glaze off of the pads. Re-lubing the caliper slides may help also.
Most brake noise comes from vibration of the pad against the caliper. Make sure the pad is seated securely.
If the car is stopping safely, sell it as is. Tell the buyer that it may need rear brakes soon. Knock $25. off the selling price.

FastShark85 · 08-22-2003, 09:54 PM

One way to try to break the glaze off is to do a few 60-0mph hard breaks, braking hard, but with just a little less pressure than is required to lock the breaks. Skidding won't do it.

Of course, make sure there's no one behind you.

scoobydugan · 08-23-2003, 10:41 AM

sounds good fastshark

Sion · 08-23-2003, 12:44 PM

91 beretta? that would be drum brakes on the rear if my memory serves me correctly. that being the case, the squealing noise is probably one of the following:

accumulated brake dust from the shoes - clean the brake assembly thoroughly and it should go away

under-adjusted shoes - if the shoes are not making full contact with the drums upon brake application, the could cause a squeal. adjust the brakes to correct.

loose/worn parts - the hardware that holds the shoes in place could be worn/loose, allowing the shoes to vibrate when braking occurs, causing noise. replace hardware to correct - also, use caliper lube on the area where the sides of the shoes rub against the backing plate.

CHECK THE FRONT BRAKES - sometimes noises from the front seem to come from the back, and vice versa. check the fronts to be sure.

grumpyolddude's advice regarding front brakes is 100% accurate too.

as for removing the "glaze" from a set of brake pads or shoes - you need to understand that glazed brakes are a result of TOO MUCH heat. if your pads or shoes are glazed, it means that they got TOO HOT too fast. doing as fastshark suggested will only increase the amount of glaze on a set of brakes.

however, when replacing brake shoes or pads, the DO need to be properly seated to the drums/rotors. this is accomplished much in the manner that fastshark described, except at lower speeds. what you are trying to do is warm them up slowly and allow them to seat into the drums/rotors. (essentially, what you are doing is sanding the pads/shoes with the drums/rotors so that the surface of the brake is a match with the surface of the drum/rotor - you are overcoming the surface level difference between the two parts. for example, if the pad is smooth but the rotor surface is slightly wavy, there will not be 100% contact between the two. after seating, the surface of the pad will match the surface of the rotor so that they make the most contact with each other).

brake seating is much more important for front pads than rear shoes. but the procedure is as follows

firm braking pressure applied at 20 mph
drive for a minute or two
firm braking pressure applied at 25 mph
drive for a min or two
firm braking pressure applied at 30 mph

repeat every 5 mph until highway speeds are reached

note: firm braking pressure means just that. not panic braking, not almost hard enough to lock the brakes, just firm even braking, just a bit harder than normal braking under regular conditions.

scoobydugan · 08-23-2003, 08:21 PM

It's very odd....I cleaned the drums totally.....it's not the front i changed them a few weeks ago...the noise is constant, not just when i apply the brakes.

08-22-2003, 01:49 PM	#1 (permalink)
scoobydugan Crazy	Identify this noise Hey guys....went to change the rear brakes....I swear I heard the trademark squeeling of the brake wear sensors....turns out that i have a little under a 1/4" of pad left....not the brakes....any idea what the noise could be? Last edited by scoobydugan; 08-22-2003 at 01:54 PM..

08-22-2003, 08:19 PM	#7 (permalink)
grumpyolddude Deliberately unfocused Location: Amazon.com and CDBaby	You might try getting the rotors resurfaced, or take some emery cloth and knock th glaze off of the pads. Re-lubing the caliper slides may help also. Most brake noise comes from vibration of the pad against the caliper. Make sure the pad is seated securely. If the car is stopping safely, sell it as is. Tell the buyer that it may need rear brakes soon. Knock $25. off the selling price. __________________ "Regret can be a harder pill to swallow than failure .With failure you at least know you gave it a chance..." David Howard

08-23-2003, 12:44 PM	#10 (permalink)
Sion Dumb all over...a little ugly on the side Location: In the room where the giant fire puffer works, and the torture never stops.	91 beretta? that would be drum brakes on the rear if my memory serves me correctly. that being the case, the squealing noise is probably one of the following: accumulated brake dust from the shoes - clean the brake assembly thoroughly and it should go away under-adjusted shoes - if the shoes are not making full contact with the drums upon brake application, the could cause a squeal. adjust the brakes to correct. loose/worn parts - the hardware that holds the shoes in place could be worn/loose, allowing the shoes to vibrate when braking occurs, causing noise. replace hardware to correct - also, use caliper lube on the area where the sides of the shoes rub against the backing plate. CHECK THE FRONT BRAKES - sometimes noises from the front seem to come from the back, and vice versa. check the fronts to be sure. grumpyolddude's advice regarding front brakes is 100% accurate too. as for removing the "glaze" from a set of brake pads or shoes - you need to understand that glazed brakes are a result of TOO MUCH heat. if your pads or shoes are glazed, it means that they got TOO HOT too fast. doing as fastshark suggested will only increase the amount of glaze on a set of brakes. however, when replacing brake shoes or pads, the DO need to be properly seated to the drums/rotors. this is accomplished much in the manner that fastshark described, except at lower speeds. what you are trying to do is warm them up slowly and allow them to seat into the drums/rotors. (essentially, what you are doing is sanding the pads/shoes with the drums/rotors so that the surface of the brake is a match with the surface of the drum/rotor - you are overcoming the surface level difference between the two parts. for example, if the pad is smooth but the rotor surface is slightly wavy, there will not be 100% contact between the two. after seating, the surface of the pad will match the surface of the rotor so that they make the most contact with each other). brake seating is much more important for front pads than rear shoes. but the procedure is as follows firm braking pressure applied at 20 mph drive for a minute or two firm braking pressure applied at 25 mph drive for a min or two firm braking pressure applied at 30 mph repeat every 5 mph until highway speeds are reached note: firm braking pressure means just that. not panic braking, not almost hard enough to lock the brakes, just firm even braking, just a bit harder than normal braking under regular conditions. __________________ He's the best, of course, of all the worst. Some wrong been done, he done it first. -fz I jus' want ta thank you...falettinme...be mice elf...agin...

08-22-2003, 01:55 PM	#2 (permalink)
Kurant Junkie Location: Don't worry about it.	If it's just the squeeling noise from the brakes it could be a flaw in the material in the pad or rotor, or 100 other things... My M3 has had squeeky brakes in one pad from the day I bought it. BMW said nothing was wrong internally, and they changed the pads and it stopped. It was a brand new car. Squeeking doesn't always mean somthing bad is going on, brakes can just squeek from flawed materials. If that's the case, it'll stop. But changing it still is never a bad idea.

08-22-2003, 02:03 PM	#3 (permalink)
otter Upright	Dirty drums can cause squeeling. Grab some brake cleaner and clean the inside of the drums, see what that does.

08-22-2003, 02:10 PM	#4 (permalink)
scoobydugan Crazy	Yeah, otter i already tried that....I'm selling the car so I would rather not put any money into it...but its only $15 for new pads....i could always explain the noise to potential buyers...anyone wanna buy a 91 chevy beretta GT?

08-22-2003, 04:17 PM	#5 (permalink)
FastShark85 Psycho Location: In the garage, under the car.	Take a high-pressure hose and wash the rotors and pads thoroughly. It does the trick for me for the first few hundred miles. Brake dust builds up and can cause squeaking. Your brake dampers may also be worn out, given the small amount of pad left.

08-22-2003, 08:06 PM	#6 (permalink)
scoobydugan Crazy	its not a small amount of pad, thats the thing, it's kind of odd actually....it almost looks like theyre brand new...I tried cleaning with a high powered hose, and i took an air chuck to clean them off...with a mask on of course

08-22-2003, 09:54 PM	#8 (permalink)
FastShark85 Psycho Location: In the garage, under the car.	One way to try to break the glaze off is to do a few 60-0mph hard breaks, braking hard, but with just a little less pressure than is required to lock the breaks. Skidding won't do it. Of course, make sure there's no one behind you.

08-23-2003, 10:41 AM	#9 (permalink)
scoobydugan Crazy	sounds good fastshark

08-23-2003, 08:21 PM	#11 (permalink)
scoobydugan Crazy	It's very odd....I cleaned the drums totally.....it's not the front i changed them a few weeks ago...the noise is constant, not just when i apply the brakes.