VW brake noise?

Check that the rotors aren't worn down.

The brake warning light came on on my old Audi A6 at one time. It was the pad wear indicator, but not from the pads being worn, but from the rotors having been worn down and leaving a ridge at the circumference of the rotor that cut the wire to the pad indicator!

Had this continued, the ridge would have contacted the metal backing of the pads.

Needless to say, the rotors were well beyond the minimum specified thickness and I replaced them.

Thomas

they ARE worn down..quite a bit..ready for changing..

i suspected this exact situation for about a month, there is a large ridge, but a local mechanic said he didn't think that was it..but i think you're on the money.. thank you..

bob

You should check the rotors more than just with a visual check. You should put dial calipers on the rotor and measure it's thickness and then compare that to the minimum thickness for the rotors.

For 40k miles, that's not bad for the front pads. It sounds like you might have metal on metal. If your rotors were machined when the brakes were done, then you probably lost quite a bit of thickness then.

If there's a ridge on the rotor from the previous pads, your mechanic should have machined that down so the new pad would not contact it, if he didn't, he didn't do a very good brake job.

-Bruce

i'm quite sure that caliper check will show the rotors need changing..i was going to do it this summer..i just wanted to make sure there wasn't somethign else (mast cyl, abs sytem, etc.) making the noise.....

they weren't machined, just pads put on..

i can't blame the mech, i wanted a cheap job done..sears did pads for 99$, VW wanted $399 for pads/rotors both, wouldn't do just pads.my fault really..

so, bruce, do you agree the ridge is causing a grinding noise possibly?

bob

Usually the cheaper front pads will make grinding noises once they've warmed up. For a VW I would only use OEM pads. The reason is that cheaper pads have impurities in them that are hard on rotors and reduce braking performance. In the end the $20 you save on pads could well cost you a new set of rotors that would have lasted two or three more sets of "good" pads.

Anyway, the noise in and of itself probably doesn't mean anything is being hurt beyond the wear they'd experience if there were no noise. You should make sure the wear indicator is hooked up.

doesn't mean anything is

there is plenty of pad left, and also i look at the pad and rotors and see nothing wrong except the rotors have a pretty big 'lip' around the edge..they WERE cheapo sears rotors, not the OEM's, wonder if they're just as you say? any way to check?

bob

I'd say that it could be making the grinding noise but only if the brake pad backing plate is in contact of that ridge or the rotor, otherwise, the ridge won't hurt anything.

My thought is if your brake pads are worn down, then yes, there's a good chance that you're getting metal on metal. Then again, that ridge shouldn't be that much higher off the surface of the rest of the rotor surface. It'd be best if you took the wheel off and did a visual check of both sides of the rotor (you said visually they don't appear to show anything wrong). It may be the inner brake pad is metal on metal while the outer brake pad still looks fine.

It seems strange that your rotors were under the minimum thickness the

*last* time you did your brake pads. I would think a brake rotor could go forever as long as it never warped and you took it easy when you machined it for brake jobs (if at all).

If you're getting a grinding noise when coming to a stop, it's possible that an anti-squeal plate or such has come loose or maybe a caliper bolt? I don't know what else it could be unless it were a wheel bearing but that would be heard under acceleration as well as deceleration.

That's all I got for now. Let me know what you find.

-Bruce

yes, the inner side, that's what i'm suspecting..i never examined that..

well, they did the back at 110k miles, and said they were too thin to machine so they replaced back rotors..so i figure the front, at 120k miles much definitely be much worse?

no bearing..but the other 2 might be the one also..i'll be at the dealer in the next wk to check out..thank you for your help..

bob