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a little help here, like model and mileage. What your hearing is the pas wear indicator. They squeel when driving and go away when you break.

The fact that your hearting one and not both may mean you have a sticking caliper.

now for the yelling :headbang:

ITS THE BREAKS DONT SECOND GUESS.

If you wait for them, to go metal to metal, that can instanly double the cost of a break job.

 

nipper

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a little help here, like model and mileage. What your hearing is the pas wear indicator. They squeel when driving and go away when you break.

The fact that your hearting one and not both may mean you have a sticking caliper.

now for the yelling :headbang:

ITS THE BREAKS DONT SECOND GUESS.

If you wait for them, to go metal to metal, that can instanly double the cost of a break job.

 

nipper

 

95 Legacy 80K Miles. Thanks for the info.

 

Now for being yelled at:mad:

 

Can't argue with your assessment.

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Been where you are now in the past. Have had the noise attributed to the wear indicators on the pads, but have also had the sticking piston in the caliper cause the same thing, all because the car didn't get the required brake fluid flush every 3 years. Water absorbs into the fluid, settles in the bottom of the caliper bore and starts rusting. Eventually the caliper will start to stick, not totally releasing from the pad when you take your foot off the brake pedal, and then you get the scraping noise, that will go away when you step on the pedal. If you take care of the problem now, and if the rust damage has not progressed too far, they may be able to be cleaned up, and with a complete flush and fluid refill be as good as new. Good Luck!

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Been where you are now in the past. Have had the noise attributed to the wear indicators on the pads, but have also had the sticking piston in the caliper cause the same thing, all because the car didn't get the required brake fluid flush every 3 years. Water absorbs into the fluid, settles in the bottom of the caliper bore and starts rusting. Eventually the caliper will start to stick, not totally releasing from the pad when you take your foot off the brake pedal, and then you get the scraping noise, that will go away when you step on the pedal. If you take care of the problem now, and if the rust damage has not progressed too far, they may be able to be cleaned up, and with a complete flush and fluid refill be as good as new. Good Luck!

 

thats odd...

I only flush every 100,000 miles. Biggest reason for sticking is rusted sliders (some mfgs even state never)

Water in the barke fluid will not cause rust, and it doesnt settle at the lowest point either. Water in the brake fluid will cause brake fade. The breaks are a sealed system. To make rust you need to have air plus water plus something that would rust. Sounds like you had another issue that caused that, like a leaking caliper or craocked dust boot.

 

 

nipper

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I agree with Nipper here. The squeal is the wear indicator.

 

I change my fluid a bit more, every 3-4 years (60-80k), but the pins are where the sticking comes from. I just did a brake job a few days ago and one of the most important part (to me, at least) is pulling the pins and insuring they are well lubed and that the protective rubber boots are in good shape. If you don't do this, you will wear one pad out in a hurry and be up for another brake job quickly.

 

FYI - I have 72k on the car and this is my first set of new pads since the dealer changed them out at 8k. I switched to Akebono PRO/ACT ultra premium ceramic pads to minimize dusting and am very happy with the pedal feel on them too. I was also exceptionally happy to see the maintainence friendly arrangement for pad and/or rotor changeout on my 02 Legacy GT.

 

Jack

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Dear Nipper,

In the last two years I have done at least five vehicles where the pistons are rusted in the caliper bore. In three of the cases, after the pistons were slowly pumped out of the caliper, the pistons and the bores were able to be cleaned up with careful scrubbing with 0000 steel wool. Because there was no visible pitting or scoring on the pistons, they were cleaned up, reinstalled and properly bled. On the other two there was too much rust damage to the pistons to be cleaned up, and remanufactured calipers were installed. Brake fluid is hygrscopic, meaning it absorbs water from the air, and water in steel brake lines and cast iron calipers means rust. This is one of the reasons why some people choose silicone brake fluid. It doesn't absorb water from the air.

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Dear Nipper,

In the last two years I have done at least five vehicles where the pistons are rusted in the caliper bore. In three of the cases, after the pistons were slowly pumped out of the caliper, the pistons and the bores were able to be cleaned up with careful scrubbing with 0000 steel wool. Because there was no visible pitting or scoring on the pistons, they were cleaned up, reinstalled and properly bled. On the other two there was too much rust damage to the pistons to be cleaned up, and remanufactured calipers were installed. Brake fluid is hygrscopic, meaning it absorbs water from the air, and water in steel brake lines and cast iron calipers means rust. This is one of the reasons why some people choose silicone brake fluid. It doesn't absorb water from the air.

 

Dear gbhrps,

I know its hydrostatic, but its so rare that something must be wrong some place else. I'm 45, done more break jobs then i would like to admit too, and have seen it only once, when the "operator" lost the cap to the master cylinder.

 

nipper

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thats odd...

I only flush every 100,000 miles. Biggest reason for sticking is rusted sliders (some mfgs even state never)

Water in the barke fluid will not cause rust, and it doesnt settle at the lowest point either. Water in the brake fluid will cause brake fade. The breaks are a sealed system. To make rust you need to have air plus water plus something that would rust. Sounds like you had another issue that caused that, like a leaking caliper or craocked dust boot.

 

 

nipper

 

Sealed system? Most Japanese cars have a bleeder hole in the brake fluid resevoir cap...if it was a truly sealed system, a vaccuum would be created as the brake fluid level drops due to pad wear and the greater extension of the caliper pistons. Older GM vehicles use that rubber bellows-type doohickey on the master cylinder cover to allow the level to drop w/o needing an air vent to the atmosphere. It's nice to know that they came up with one good idea at GM!

If not rust, what causes caliper pistons to stick? Surely you've seen this in cars which have good dust boots? It seems to happen most often in older cars which have been left sitting.

 

Nathan

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