[factrzero]

I've only got 500kms on my car now. I have the sedan GT/GFX package with the 17" rims/wheels.

Everytime I break, I hear the rear rotors making a grinding noise, and I feel a very little amount of vibration in the break peddle. Is this normal working-in wear or a bad set of rotors/pads?

 

[vaBooM]

No. That means the pads are driving themselves into the rotor. Run your finger along the surface of the rotor. If there is any indents, the rotor will need to be replaces.

Could need a good pressure wash to dislodge any pebbles or debris.

 

[factrzero]

Curious

The front rotors have no indents, or lines. The rear rotors have lines going around right where the caliper/pads grab. It doesn't feel like the lines are indented, it feels like they're sticking out.

 

[M3-GT]

Does this happen just at the start of a day or after a while you haven't taken you car or it does it all the time?

 

[cebo0650]

I noticed the same thing, I have about 240km on my car now. Some say that it will go away as the rotors and break pads wear-in and become smooth...I certainly hope so, if not I'm taking it to my dealer to have it checked out. As far as I know rotors shouldn't have any lines or indents in them. I also noticed that I have a lot more break dust on my rear wheels, which is wierd. Usually there is more on the front ones.

 

[Black7]

I'm hearing it on the rears as well (the odd squeek and a little rough) - I'm going to "wait and see" for the moment but let's keep each other posted via this thread

 

[factrzero]

All the time

It always makes the noise whether the rotors have been warmed up a bit or not in use. I think I'll wait about 1500kms, that's just 500 more than the break-in. If it continues past this point, it's probably worth a look. No need to bother them too early

 

[factrzero]

Incedently

There's more brake dust on my rear rotors as well, and only the rears have the visible streaks, indented lines forming but the fronts do not. Curious. I think I'll at least have the dealership take a look. After that if it continues past 1500, it's go time

 

[M3 Craz]

yah,

I am close to approching 1500km and I ONLY hear discs sqeak in reverse at very low speed.

as for break dust, more heavy on the back with noticeable break dust.

and I think I am seeing streak on one of my rear disc as well weird.........

gotta go see the dealership about it really soon

 

[DJ Spencer]

Blah!

Yes, I've hit 600 miles (you do the math) and started getting the grind/squeak out of the back. Haven't checked for lines or grooves, but they are for sure only coming from the back of the car.

Typically, if I hear it, the weather is cold (for me, below 40 degrees F).

 

[factrzero]

Squeek

Yeah, I hear it ALL the time as a squeek/grind now in the cold. It's -11 celcius here, pretty bitter cold. I'm assuming at this point that this is regular break-in behaviour.

I was told to wait about 1500kms. The squeek/grind should be GONE by this point. If not, take it back to the dealership before the real damage is done.

 

[sky078]

my 3 is approaching 3500KM and i experienced all the things that you guys said.. esp squeaky noice and more brake dust .. (Rear brakes..)
so should i go to dealership to check it out? or is it normal for everybody?

 

[M3-GT]

Seems like it's like this for everyone but I will still ask my dealer wth is that when I do my first oil change at 5000k.

 

[rpc180]

Had mine in for an oil change and a few other things. A few days ago I noticed that the rear rotors felt a bit rough, compared to the glass smooth surface of the front rotors this is in addition to the brake dust question. Anyway, I had them look at that too, the sheet says "brakes check out O.K." Job code was 51MAZ.

 

[factrzero]

Hmm

OH well,

I guess that settles that question

 

[crzyone01]

Ok just to answer a few quesitons, the more brake dust is caused mainly by the back not being ventilated(the ventilation holes on the front collect alot of the dust put off), and possibly they used a different type of pad in the back but unlikely. As far as the lines on the back, if they are small raised lines you are fine this is a cause of the rear brakes not receiving anywhere near the amt. of force the front brakes do(which is why the fornt brakes are glassy smooth). But if there are small rough lines engraved into your discs then you have some debris caught in between your pad and rotor pressure washing will remove most of it. As for the squeaking see my post in the other topic on brakes

- Phil

P.S. Safety Phil's tip o' the day is when feeling your rotors for imperfections only touch them when you have not driven the car i nthe past 2 hours at least, they become hot enough to melt your flesh(sounds fun doesn't it) it won't stick to the rotor though because of how smooth it is, it will just glide right off and you will be missing part of your finger, don't worry about any bleeding though because it actually cauterizes(spelling ?) it for you.

 

[rpc180]

That sounds like a good reason for the rear brake dust to me! That also sounds like a good reason for the rear brake rotor grooves as well! That also sonds like a good reason for not touching the rotors as well!

You're good. Perhaps too good :twisted:

 

[Kazbaeden]

don't worry about any bleeding though because it actually cauterizes(spelling ?) it for you.

How thoughtful...

 

[DJ Spencer]

I enjoyed the fact that it will just glide off and I won't have a finger anymore....

Here kitty, kitty, kitty.....

 

[funkyfreshmonke]

when my dad backed out of my driveway tonight i herad a loud SQUEEAAAKK...im pretty sure it was form the brakes....and i havent used the car for like 2 days now and its been about 40-50 degrees F at night here and about low 60s to high 60s during the day....do u guys think its just squeaking becuz of non use + cold, or what else could it be? andmy dad washed it yesterday and who knows what he did to it....