twisted

It does not appear that the cracks go into the holes in the rotors, like on a steal rotor. The dealer looked at it and said they thought it was OK. So what does everyone else think? Does anyone have a contact number for the Mid West/Chicago region PCNA rep? Think they might like to see this? Also car had only about 300-400 mile on it when I showed it to the dealer last weekend, photo taken this morning after returning from trip, car now has about 800+ mile on it. This is from the left front rotor. The right front rotor does not look like this but does have one or two small spider cracks. Rear rotors still look like the pads are still bedding in and have no signs of this.

Sloth

IMHO, no way should they look like that after only 800 miles. Were you at the track or did you do anything else that might have caused some problems? Can you feel the cracks with your fingernail? Have the cracks gotten larger since you first noticed them? Are the cracks all around or just in one spot on the rotor?

Regardless, do keep an eye on it and try to get them to replace under warranty. Brakes are to important and these rotors are to expensive to let them go. Do let us know if anything comes of this.

FYI... no cracks on these rotors from a TT used at the production facility test track in Leipzig.

twisted

Street use only. Just following break-in procedures. You really can not feel them. Cracks have not really become bigger, even after my 400 mile trip.

One idea I'm wondering ... if it's pad transfer material (glaze) that has cracked, pads that are on the car are stock yellow pads, from the exposed backing plate it says Pagid P90-2

01 C4 Cab NYC

Looks like the picture from Leipzig is a well worn set of rotors. Twisted, I'd venture to say that your rotors are fine, the cracks are just on the surface, and once they wear in a bit, the cracks will go away...

LA964

My only experience here is w/race cars. All I can say is when you look at the carbon disc on a race car you'll be shocked to see how chipped and cracked they get. Even out of the box they don't look real nice. You can't compare these to steel discs.
Good luck.

FixedWing

That looks nothing like any failure I've ever seen. I would think it has to be a manufacturing defect. The nature if the carbon-ceramic material is that it is strong in all directions. Cracks do no propagate the way that they do with cast iron. The fibres in the material will stop the crack before that happens.

Can you be sure that the cracks were not there the day you collected the car?

My assumption would be that the cracks go all the way through. I have no clue whether that is a safety issue (i.e. the rotor is at risk of coming apart).

Stephen

twisted

I can not be sure that they were not there when the I picked up the car.

Also I rechecked the rotor and when one runs his finger nail across the surface the cracks catch the nail / get hung up in / stopped by the cracks.

Dealer service department is reviewing the pictures I have taken and have forwarded them on the to local PCNA rep for review.

twisted

A few more shots, shows the cracks that are connecting the holes up and down but ALSO across the rotor surface from hole to hole.



This pic shows the crack from the other most hole on the lower row to the third hole in on the middle row to the second to last hole in the top row. If you look closely you can see the cracks in the middle row of holes connecting one hole to the other.

twisted

I outlined the cracks ....

twisted

The local PCNA Tech Rep has reviewed and forwarded on to Porsche the first set of pictures that where taken. Current position from the local Rep is normal cracks. Today I had the car aligned and we pulled the wheel to further check the status of the cracks. As you can see from the attached picture the cracks are all over the surface of the rotor, some of them do catch one's finger nail, and viewing into the drilled holes where cracks are .. the cracks are only surface (not like a crack one see on a steal rotor) about a 0.5 mm depth if that.

Sloth

Thanks for the situation update and photos. Please let us know what the outcome is.

Regards

FixedWing

Twist,

How do you know that the cracks are only surface deep? What do the inside surfaces look like??

From the photo you can see that the pads still have their paint on them. No way that those rotors have ever been overheated. The yellow paint on the pads is the first thing to go.

So how do you feel about all of this? Are you willing to accept that this is "normal" if PAG says so? They tried to convince me that my rotors were normal. That stopped when I took the service manager for a little joy ride in rush-hour highway traffic and showed him how the car would pull across lanes at 260 km/h when the brakes were heating unevenly. I heard later that he couldn't sleep that night. But at least I didn't hear any more b.s. about "normal".

There is powerful contingent within PAG that has decreed they work. Those declaring that the King has no clothes do so at their peril.

Stephen

Steve in FL

FixedWing: 260 km/h rush hour traffic? I don't think I'd have slept after that even if my car didn't want to pull across lanes under braking.

twisted

Today we looked inside, outside, around etc and could not find any cracks into the rotor, just surface cracks. We check the other front rotor and it too has a few cracks on the surface but not as bad as this one. How do I feel about it, not real happy, kinda mixed at times. As to the paint on the edge of the pads, still looks new, so no real signs of any heat. FWIW we were able to see 'Pagid P90-2' marked on the front pads.

FixedWing

I know this photo has been shown before but these are Pagid P40 pads which were originally painted with the same yellow paint. As you can see, they aren't yellow anymore. The paint will go well below the maximum temp of the pads and so serves as a sign that you are getting close. If the pads remain their nice colour of yellow then neither the pads or rotors should be a problem. When it starts to go it is quite obvious from outside. They will go brown and then black.

Stephen