stressed marked rotors

[boots]

Hey, who on here had stressed cracks coming from the holes in the rotors and got them replaced. I cant find the thread. I noticed some stress cracks on mine so guys check yours. Mine were on the front rotors. It might not be a problem as I think the rotors with holes in them are prone for stress cracks.

[M6-Coupe]

I guess @335iRlz

[M5Rlz]

Originally Posted by M6-Coupe

I guess @335iRlz

You guessed right mine also had blue heat spots from stopping from XXX so much lol it was on all fours, they had to do a PUMA case to replace everything.

http://f10.m5post.com/forums/showthread.php?t=994215

[boots]

Thanks

[M6-Coupe]

Originally Posted by 335iRlz

You guessed right mine also had blue heat spots from stopping from XXX so much lol it was on all fours, they had to do a PUMA case to replace everything.

http://f10.m5post.com/forums/showthread.php?t=994215

I'm always right kid

[boots]

BMW replaced my stressed rotors last week w no complaints for a one time only. They did mention that the stress fractures will return at some point. I'm ok w this.

[RPiM5]

Mine have been cracked for a long time. A few months ago my dealer said they wouldn't replace them even though they had cracks all over them because the rotors themselves weren't below spec. Now they are below spec, so I guess I can get them changed. Lol!

[boots]

Dave get them done b4 your warrantee runs out!

[thebishman]

Small cracks propagating from the rotors are no big deal and won't compromise braking performance at all, plus it's pretty common with drilled rotors stopping heavy cars from high speeds. As long as you can't 'catch' your fingernail in the crack, or they don't extend from one drill hole to the other, you are fine.
However if BMW are willing to replace them under warranty, I'd go for it as well.
Bish

[M6-Coupe]

Originally Posted by thebishman

Small cracks propagating from the rotors are no big deal and won't compromise braking performance at all, plus it's pretty common with drilled rotors stopping heavy cars from high speeds. As long as you can't 'catch' your fingernail in the crack, or they don't extend from one drill hole to the other, you are fine.
However if BMW are willing to replace them under warranty, I'd go for it as well.
Bish

Agreed. It's the nature of drilled steel rotors for high performance braking systems and is normal. I have seen those small cracks on my car's rotor too (I have never tracked my M6 or doing constantly hard braking)... I asked my SA to check it out weeks ago and he answered the same thing you mentioned. The amount of heat and stress on these rotors may cause those cracks around drilled holes and that's why those holes are there to dissipate the heat.

watch this video about M3 @ 4:45 and see what's going on when you depress the brake pedal...