RJFabCab

The actual rotor surface looks to have some life left (but not much). Unfortunately, you have a crack within the slot at the the thinnest part of the rotor... and that crack looks long and deep.

I would rebuild now.

Plus, you don't want someone at tech to call you on it, and then you're off to the garage for rotor work as your session is lost.

Edit: I'd be shocked if that's pad build up. That looks like a crack to me. Keep us posted!

Seth Thomas

REPLACE THEM ASAP! Those rotors are shot especially with the crack you are seeing in the slot. Don't even keep these as spares. My reason behind this is you have a crack forming that will only get worse the first time out on the track. You will be replacing them before the weekend is out and I will bet you will be replacing them after the first session if the rotor doesn't explode while on track.

The expense of changing the rotors is a lot cheaper than the expense of smashing your car up because you tried to save a few dollars getting a little bit more time out of a part. Why risk it when you will be replacing them very soon.

Edit: Just saw the post about pad deposit instead of a crack. That could be the case with the appearance of a crack in the slot. Still I would change the rotors based on the appearance of them. The surface cracks are getting very close to the edge of the rotor. These will only keep spreading within the first day of the track. I still say you will be replacing the rotor before the end of the first day.

KOAN

I also think that is brake pad deposit in the slot. It is a little hard to know on non-drilled rotors when to pull the plug. I do it when the cracks extend to the outer or inner edge, 2 of the other criteria Porsche gives for replacement. That may or may not happen in your next weekend. However, since you are unsure, I'd change them. I had some dead sets that look very similar to this. I agree with others who say the downside of being wrong isn't worth the small amount you'll save by running them one more time.

Macster

Why not contact the makers of the rotor and supply a pic and hear back what the maker has to say about the condition?

I visited Girodisc's site and it mentions drilled rotors developing cracks which is bad. I can't imagine it is any less bad on slotted rotors.

Sincerely,

Macster.

SH || NC

PAD MATERIAL

Just scraped it out with a long flat head screwdriver. Same kind of deposits on the passenger side. I should have checked before starting the thread. With regard to the surface cracks - they don't bother me.

Thanks all.