A little help from you car mechanics

[Z3Dreamer]

My old reliable - 2003 Subaru Legacy L developed a sound in the front end, maybe on the left side. It occurs when the car is cold and the brakes are applied. After about 15 miles of driving, the sound goes away. Over months, it is getting worse.

I brought the car into local shop that replaced the brakes 10,000 miles ago. Of course, it makes no sound when their mechanics drive it. I have left the car several times....

What is it? (Other than hearing impaired mechanics)

[golfnut]

Just a guess. Ball joints?

[MichaelB]

Quote:

Originally Posted by golfnut Just a guess. Ball joints?

Is that the Subaru version of ED ?

[RAE]

Can you describe what the sound is like? Does it sound like a rattling/vibrating piece of thin metal, perhaps? If so, it could be something within the brake assembly, especially since you hear the noise when the brakes are applied.

[Z3Dreamer]

When you apply the brakes, a grinding or scaping is occurring. And the sound changes as the whole thing rotates.

[ShokWaveRider]

Run your fingers over the rotor, is it smooth? If not you could have grit or damaged break pads, if it is smooth you could have the beginings of such.

I would take the break pads out, inspect them and the rotor, clean everything with break cleaner, maybe even sand down the pads, use caliper grease and reassemble. If it still makes a racket, I would change the pads and have the rotor ground.

While you are there check the Wheel Bearings and bushings.

[Ducati52]

If you don't drive the car often, it could simply be the rust on the rotors causing the noise until the pads sweep it away. Usually doesn't last 15 miles, though. Can you see any scoring on the rotors? If something is actually grinding, you'll see scoring on the rotors.

I've had front wheel bearings on front-wheel-drive/all-wheel-drive cars make intermittent grinding noises that change when you hit the brakes, so if the brakes check out, that might be another avenue to explore.

[Gumby]

Quote:

Originally Posted by ShokWaveRider Run your fingers over the rotor, is it smooth? If not you could have grit or damaged break pads, if it is smooth you could have the beginings of such. I would take the break pads out, inspect them and the rotor, clean everything with break cleaner, maybe even sand down the pads, use caliper grease and reassemble. If it still makes a racket, I would change the pads and have the rotor ground. While you are there check the Wheel Bearings and bushings.

Brake rotors are so cheap now that it makes more sense to buy new ones if necessary rather than turn the old ones.

[mountainsoft]

Quote:

Originally Posted by ShokWaveRider I would take the break pads out, inspect them and the rotor, clean everything with break cleaner, maybe even sand down the pads, use caliper grease and reassemble. If it still makes a racket, I would change the pads and have the rotor ground.

Agreed, if the grinding/scraping noise only occurs while braking, it's most likely an issue with the brakes. Since you had them replaced recently I would tend to think the pads have cracked or otherwise failed, but there's no way to know without pulling things apart and looking. Check the rotor for scoring or warping, and replace if needed.

It's also possible you have some kind of debris in the brake mechanism. My wife once had a very loud scraping sound appear when we were on a trip. It sounded like the whole front end was grinding away. We stopped at a rest area and pulled the wheel off to discover a tiny pea sized pebble trapped between the brake rotor and dust shield. I removed the tiny pebble and the sound went away.

[FI50]

Sounds similar to an issue I had. Turned out to be the brake caliper keeps getting stucked.

[street]

It could be a few things. First if you had a place to go and go in reverse and apply your breaks while moving backwards. Do this a few times and make sure you apply and hold lightly as you backup. If you had your brakes done 10K miles ago I would hardly doubt it would need new pads etc.. Try this and see if it stops. They will self adjust on most outfits and doing so could dislodge a small pebble or material that has lodged in there.

[ncbill]

I also vote for something brake related...e.g. rusty rotor, stuck caliper.

[ShokWaveRider]

I think the problem is the OP does not do the work themselves and has to rely on a "Stealer" Dealer or Maintenance shop to do it for them. Makes it expensive.

[wolf]

Try another mechanic. Ask friends, for referral. Should be easy fix.

Since the noise is coming from a single location!

[JoeWras]

An outside possibility is a wheel bearing issue. Subarus are great, but wheel bearings usually need replacement at such an age.

Problem is, the bearing noise rarely goes away. Braking can change the geometry and make it worse, but you are more likely to notice a difference while turning. The fact your noise goes away mostly rules out bearings.

Just throwing it out there as a low probability possibility...

[ncbill]

Quote:

Originally Posted by JoeWras An outside possibility is a wheel bearing issue. Subarus are great, but wheel bearings usually need replacement at such an age. Problem is, the bearing noise rarely goes away. Braking can change the geometry and make it worse, but you are more likely to notice a difference while turning. The fact your noise goes away mostly rules out bearings. Just throwing it out there as a low probability possibility...

Expensive though...IIRC, the wheel bearing unit assembly on our 20+ year old Subaru Legacy was a few hundred bucks just for the part.

[Breedlove]

Question , does the car shimmy ( shake ) when you apply brakes . If it does it could be warped rotors . Did you have your rotors replaced when they replaced the pads . Todays rotors are real cheap and often warp . It will sound like something hitting another part and shake . Won't happen all the time only when you have been driving for a while or you apply the brakes hard at a good speed . No big deal . A wheel bearing would squeal like a pig and get louder the faster you go .

[Bamaman]

I had a couple of cars sitting around--barely driven for a year or so. Hit the pedal, and they were hard to stop.

All of the hardware on the brake pads rusted, and they didn't move freely. I removed, lightly sanded and regreased the hardware and it's all fine now.

[Jerry1]

Quote:

Originally Posted by Z3Dreamer When you apply the brakes, a grinding or scaping is occurring. And the sound changes as the whole thing rotates.

I’m thinking surface rust on your rotor. Second would be the break caliper sticking. The rust will wear off pretty quickly though so after the first breaking or so, sound should be gone. Break caliper sticking is something someone who did your breaks should be able to verify rather easily.

I would take a look at the rotor before you drive it and see what it looks like before you drive and when you park. If that’s not it, I would take it to a different mechanic. These are your breaks after all. You need to get to the bottom of this.

[Z3Dreamer]

OP here. The answer is....due to me only driving 3,000 miles per year and leaving it outside, the rotors are full of rust. I, kind of, took your advice and went by another mechanic (the dealer.) At first they were recommending replacing everything (rotors, pads and maybe calipers). But I said: "Hey, if I do as you said, and I don't drive it much, won't your new equipment be all rusty in a year?" Service adviser said: "Yes". They also added that my 164,000 mile car leaks oil. Where is my surprise face? And they wanted to replace all kind of things to fix the oil leak. You know, I have the oil changed once a year and it is still relatively full, so why spend a gazillion on new seals?

But for $51, it was worth it for them to tell me that it is nothing too serious.

Thanks for your posts.