07, manual, 97000 km. Daily driven, Canadian climate.

All rotors OEM from day 1, have not changed. Pads changed at 70,000 km to Hawk Ceramics all four corners.

Grinding noise appears on brake application, especially noticable from a cold start after the car has been sitting for awhile outside. Goes away slightly, but still audible on light to medium pressure. On hard braking, no noise present. Noise appears to come from passenger side front. No reduction in braking performance. Although all stops now have a cyclicable shuddering (like a slight/fant rocking/back and forth motion) coming to a stop. Steering wheel does not move left/right. But I could feel the car stuttering to a stop ever so slightly (not fully smooth).

This has started to happen a month ago, and so last week had the brakes serviced as per below, and still didn't fix it.

At 96000 km, had brake fluids changed, lines flushed, brake caliper pins cleaned/lubricated. Pads are inspected/cleaned (of course okay, because changed only 27000 km ago).


Any ideas? Is it simply just I need new rotors with this mileage?

 

It's possible that it's the rotors. How are your driving habits?

Does this happen when the brakes are cold? What about after they have warmed up?

 

I don't use brakes that often as I rev-match downshift a lot. There's a lot of stop and go traffic in toronto though. But I mean, this hasn't happened ever before in my 4+ years of ownership, just started now.

Like I said in the post, it happens loudest when they are cold, when warmed up a bit after a few applications driving, the noise reduces, but it's still there.

 

When you changed your pads did you bother to machine the rotors? On other cars when it comes time for a pad change I either get the rotors machined or buy new ones(last car they cost less than $20 each) so they can brake correctly. If you were running regular oem pads and then switched to ceramic you should have probably cleaned your rotors. It is doubtful that your new flat pads lined up perfectly to a rotor with 70km on it.

Right now I can feel that stuttering stop you get as well, its almost like you can feel the brakes engaging and disengaging ever so slightly even on slow stops. This only recently happened to me but I can feel my front rotors and they are both kind of ugly feeling. Many slight dips up and won and have a big lip on the edge and I am only at 36k miles. My rear rotors look MUCH better.

I am thinking the fix for both you and me is new rotors on the front, but have you actually inspected yours yet? You can get the rocking that you and I described from uneven brake deposits on rotors, but there may be other causes.

 

I inspected myself, there are minor ridges on all 4 rotors. I did not machine them at all from day 1.

Also, I noticed that when I have the car up on a jack, and I try to spin my front right wheel, the wheel doesn't spin smoothly. The rim is torqued correctly to spec and in the correct pattern. You can hear the brake pad rubbing against the disc in a cyclical fashion as it spins. Does this mean they are warped? (lateral run out)?

 

my guess is your rotors are warped
i used to have a c230k and changed the pads and didnt chang rotors and i would hear a screeching noise and felt the rotors and they werent a smooth finish
didnt get a chance to change rotors cuz i totalled it LOL

 

Ok I just took some measurements with a vernier caliper. Fronts right is 23.5 mm. Front left is 23.7 mm. Rear right is 17.8 mm. Rear left is 17.9 mm

What do you guys think? Am I cutting it too close to the spec 22 mm and 16 mm front and rear respectively?

 

Really? No one?

 

what about the runout?

get an indicator.

 

I don't have the tools to get that measurement, and if I took it to a shop, it would cost some money, which might as well be used towards replacing it.

Can my question be answered without anymore money being spent?

 

http://www.harborfreight.com/1-inch-...cator-623.html

http://www.harborfreight.com/multipo...ment-5645.html

 

Is this your first winter on the pads by chance? Based on your mileage it seems possible that it would be. The ceramic pads take longer to warm then OEM and they will squeak as you are describing.

Another option for your problem is something I lived with for a while until I had someone look at the install job. They found that a retaining clip was incorrectly installed on one rotor which caused a grind as the pad actually hit the inside hub. Once the clip was reversed no more rub and no more annoying grinding sound.

 

This is the second winter I have had them. Pads were installed sept2010.