Berringer

On my recent brake replacement the rotors had to be replaced prematurely due to what my mechanic explained as glazed rotors. They had no lip dug into them or noticeable "wear". They made a very annoying sqeal though, which is what took me to the shop. Explanation: frequent light braking (not track use) had caused the rotors to be basically polished to a mirror finish. This was causing a very annoying squeal, similar to what you might hear in lesser cars' brake pad wear indicators. The idea is that it is similar to running your finger over a wine glass.
The pads had not worn to the sensors yet (15% left), but sound was one I could feel in my teeth when pulling up to a stop sign. I asked him about simply replacing the pads, but he said it would not fix the squeal unless the rotors were replaced.
So the question is... Is this common? I've never heard of such a thing, but my mechanic felt like it was a pretty common issue for cars with heavy city driving (traffic). Do you think this could be caused by cheap pads?

It is important to mention that this is an extremely reputable shop, endorsed by PCA and most of the P-car owners I know.

Please discuss.

LexVan

Drive faster. Brake harder. Solved.

Berringer

I agree with that solution! I just purchased the car in December with 28k miles and inherited the issue. I have to say I can't complain about the "light" use of my predecessor, at least in regard to the brakes.

LexVan

I bet this will be a non issue for you going forward. Enjoy the new toy. Your avatar looks great.

CORSASCHNELL

Yes braking hard occasionally is a good idea to avoid this issue, just make sure the guy behind you is far away since the 911 brakes are extremely efficient.

JW911

Glazed rotors can be cured by re-bedding the brakes or you could rub some rough emory paper across the rotor to cut up the glaze. Definitely not necessary to replace the rotors.

aviography

+1, depends on how handy of a DIY'er you are, I would run abrasive wheel, the flexible ones, not a grinding stone type, in a power drill to break down the surface glaze and put the rotors back on.

PHX 911

I call BS.
Maybe light braking glazed the pads or deposited a thin coating on the caliper, but no way you impacted the integrity of the steel rotor, unless you did the converse, i.e., overheated them.
Sounds like at the most you needed was a scotch bright to knock whatever surface accumulation off the caliper.

cvtbenhogan

+1. You could sell them on.

Mumbles

If the rotors are not warped and have plenty of life left in them, rough the surface and give them a try. What ya gotta loose ?

stronbl

+2 on the re-bedding -- This would have been my first plan to solve it before replacement. Unless there is damage or warping of the rotor you should be able to get them back to an unglazed state. Scrubbing with some brake solvent (CRC) may help too. You could always try a more agressive brake pad, which would require you to bed the new pads anyway; the more agressive pad should scrub the rotor as well. Only problem is you will eventually have to replace the rotors and perhaps sooner than normal.

mdrums

Yep, exactly what I was going to say.

1- run the rough emory sand paper of the rotors
2- spray down with brake clean fluid
3- go find a deserted country road and brake hard enough to engage ABS....do this about 5-10 times. If you've never tracked a car then you might not understand this experience but you will need to get the car up to highway speeds and quickly squeeze the brakes on very very hard.

Edgy01

Give me a few minutes with your car and the problem can be solved.

The key is to brake later from now on!

mattyf

Hilarious, but so true. I use this the technique all the time. It sometimes gets me in trouble when I drive the wife's Benz, not quite the same stopping distance

Hella-Buggin'

My wife's Audi started to squeal shortly after we bought it. I called the service department and he asked me if my wife babied the brakes. I said probably and he suggested I take the car out solo, get on the freeway, take an off ramp and wij nobody behind me to get on the brakes hard enough to kick in the abs. He said do it four times and if it still squeals to bring it in. Sure enough, it stopped squealing and I told my wife I flexed her brakes. Now every 6 months or so she says I need to fix them again. ;-)