Grinding Brakes

It is possible that something ( pebble ) has lodged in the caliper area. Can you see anything from wheel side that may indicate an imperfection on the rotor surface?
Take a photo of the wheel you hear the noise coming from and post it up. I would be happy to take a look and see if I can tell from a photo.

Also, any spirited driving leading up to the noise showing up?

I cannot say I have heard ( no pun intended ) of this concern , that did not end up being something caught in between the two surfaces.

It happens, just not often.

S

 

It definitely can happen if you drive over a road that has a lot of small rocks on it. Sometimes this happens after they have put a new surface on a road that is tar and rocks as opposed to asphalt. Those little rocks go everywhere and I had it happen a couple of times on different vehicles. It's pretty aggravating.

 

Sometimes washing the rotors with a little warm water will help.
Do not use any soap or cleaner unless it is specifically approved by Brembo.

One can easily measure the pad thickness. The minimum thickness is around 3mm. Usually the fronts wear sooner than the rears. With such little mileage, virtually impossible.

 

As already mentioned, make sure your brakes are clean and not dusty - just use water, do not use any cleaner as they can damage the brakes. BTW, scratches caused by trapped pebbles/stones can be lethal for CCM rotors. Don't drive on loose gravel if you can avoid it. Stop the car and check if you hear loud noises from the brakes.

CCM brakes also need to be used HARD from time to time. If you drive in an urban environment you may not have occasion to do that. I always exercise my brakes on a regular basis. I will find isolated straight stretches of safe roads, get the car up to "high speeds" and slam HARD on the brakes, hauling the car done to about 30-40 kph and then let off on the brakes and NOT immediately come to a full stop. If the opportunity affords, I do this several times while I roll the car between runs. I don't come to a full stop when I do these runs. I have not had a persistent noise issues with my Cali30 (16.5k kms). The most they would do is make a tiny squeak for a split second just before coming to a full stop. A good occasion to do this is on a supervised track day - they won't wear the pads much if you only track the car a couple of times a year.

 

I don’t have a lot of experience with Ferrari CCB (I’m new to Ferrari) but I do with Porsche’s system and that may or may not be relevant here. This technology is really sensitive to warm up and cool down when you drive them hard, and I’ve learned that when I do a track day I need to wrap up my sessions with a 2 lap no brake cool down or the brakes will emit a god awfull grinding noise that sounds and feels like metal on metal for traditional brakes. When I drive hard up the mountains where I live, the brakes are prone to noise if I don’t follow a similar cool down period before full stop but it is not even close to how bad it is after a track day. Fortunately, everything I have learned about this and the people I have talked with who know these brakes better than I will all say that it does self-correct and aside from being irritating, does not cause damage. However, they also say that if you don’t treat these brakes with some respect, they will not work properly if you don’t warm up and over time the rotors can delaminate in addition to prematurely wearing the pads. Rocks are an issue, my track buddy went off track with his 458 and chipped his rotors which ended up being a $25k repair for just the front axle.

 

IMO, it's always prudent to do a couple of kms of cool down at the end of a drive. However, I don't think you need to completely stay off the brakes to perform the process. Conservative speeds for the conditions and normal braking should be fine.

I suspect the awful noises are usually caused by haphazard accumulation of fine dust which result in minute high frequency vibrations as the pad and rotor surfaces make initial contact (bite). Noise is prevented when the pads and rotors are properly bedded-in but haphazard accumulation of dust can mess this up. A proper bedding process creates a smooth even transfer layer of material which prevents noise and improves both low-speed and high-speed braking performances. Uneven transfer layers causes minute chattering which creates the high-pitched brake squeals. Uneven transfer layers can be created by haphazard bedding-in of fine brake dust.

Brake noise (ANY NOISE) is a sign of energy release, in this case, caused by vibrations, which will result in higher running temperatures... which as you asserted, can also potentially delaminate (the surface ceramic layer) of the CCM brakes. CCM stands for Carbon-Ceramic Brakes. Our CCM rotors are structurally carbon but has a ceramic top surface layer - if you damage or delaminate the ceramic layer of the rotors, they're finished! Ditto for Pcar PCCBs.

So while CCM brakes last a long time they do wear so dust will come off CCM pads and rotors, much more so from the pads as they wear much more quickly than rotors. Hard braking causes more wear, releases more dust. Cool-down allows the dust to get blown or pushed off without creating a fresh (and potentially uneven) transfer layer. It's high temperatures that melt the dust and create a transfer layer therefore to prevent the creation of an uneven transfer layer after you create a lot of brake dust from hard braking, you either do a proper bedding-in sequence or you drive and brake conservatively to lose the dust. Normally, the proper ventilation design of your car's brakes should accomplish this but I agree it is always a good practice to cool down before you put the car away.

The good news about brake squeals is that you can eliminate the noise by re-bedding-in your brakes. This is done by consciously braking hard from high speeds, slowing to about 30 kph without stopping and repeating the process a few times. This creates some brake dust, melts it into a smooth transfer layer, cools it down to make it "cure", avoids putting an impression of the brake pad (on the transfer layer) by not actually stopping (very important). Release the brakes as you reach the low 30 kph speed.

As for rocks or pebbles getting caught in your CCM brakes, stay the hell away from gravel or at least drive very carefully over it.