Squeaking Cali Brakes

Isn't that a known issue with carbon ceramics?

 

Not all CCM brakes squeal (mine don't) and even iron brakes will sometimes squeak/squeal so I think the problem has to do with the particular set of brakes.

My understanding is that modern brakes/pads can work in 2 ways - by abrasive friction and by cohesive friction. Abrasive friction is the old-fashioned way of brake pads abrading the rotor surface whereby the different materials in the brake pads (and rotors eventually) are worn down by physically rubbing against the rotor surfaces. This braking effect is normally felt at urban driving speeds.

Modern brakes can also work by cohesive friction which is more effective than abrasive friction. Cohesive friction is only made possible after the pads and rotors have been properly bedded. Bedding and highspeed braking (abrasive friction between new pads and clean rotors) lay down successive layers of pad material onto the rotors. Cohesive friction then works by repeated molecular bonding and sheering of bonds between the pads and layers of identical pad material on the rotors. This works better once the brakes are adequately warmed up as in highway speed braking. CCM brakes require higher temperatures to achieve bedding because of their innate heat resistance quality compared to regular brakes so the bedding process is more involving.

In your situation, I suspect possible causes may be either the bedding was insufficient or there is some instability between your pads and rotors (i.e. if the pads are allowed to vibrate at high frequency) which causes a rapid breakdown of the bedded layers on the rotors when you brake at low speeds. Low speed braking is achieved with lower clamping forces so the pads may not be held in as stable a manner as when you brake at high speeds. High frequency vibrations that the lower clamping forces do not dampen at low speeds may cause excessive abrasive friction and undo whatever amount of bedding you may have performed. In iron brake cars some pads may also do a better job of dampening vibrations.

I think this explanation may correlate with the frequent advice from garages to brake HARD and drive the car on at highway speeds on a regular basis. The bedded layers will wear down in time so you also need to continually replace the bedded layers, with high speed and repeated hard braking where you can generate enough heat to perform the task.

So in the absence of other suggestions, perhaps you should make sure your pads are fastened correctly (tightly and properly-aligned) in the calipers so they cannot vibrate when applied. If the pads do not vibrate then you may have to review your bedding procedure with the pad supplier.

 

Squeaking/squealing is actually caused by high frequency vibrations.

These vibrations can be due to pads that aren't sufficiently fastened or due to run-out on the rotor surface that would otherwise have been eliminated by proper bedding.

 

This is a known problem or unwanted symptom with the CC brake design by Brembo for the Cali.

There was a 'fix' attempted with a modified disc for the rears but not the fronts.

However, the squeak persisted in spite of this modification.

This problem is not an issue with the 458. I don't know if the pads from the 458 brake could be used in the Cali.

I would wager that this squeak will not be a problem in the Cali T

 

As an previous owner of a Cali and currently a 458 spider I can vouch for this. Similar driving habits with both ride. Cali squeaked like a *****. Embarrassing in covered parking garages. Tried to bed brakes numerous times to no prolonged benefit. Have not experienced one squeak from spider in 5 months of ownership. YMMV.

 

The T is supposed to stop 3 feet shorter from 100kph and will likely feature 3rd Gen CCM brakes. The 458 front brakes use different pads from the Cali, ditto with the rears.

Apparently, there are also 2 different SKUs mentioned for replacement front discs for the Cali - look it up on Ricambi: 251484 appears to be an older SKU and its replacement appears to be 257101. The same arrangement is repeated with the rear brakes for the old Cali. So it looks like the factory may have made changes to the brakes in the Cali30. The factory normally makes extra parts to hold as parts inventory whenever they come out with a new car. The older SKUs may be inventory left over from the original Cali build and would explain why the Ricambi listing indicates the newer (257101) parts are "Applicable after depletion of 251484" and the 257101 parts are themselves "Valid till stock exhaustion".

As I said the brakes in my Cali30 don't make any noise and they haul the car down very well. Now that you mention it, my salesman made a point of reassuring me I would have no problems with the brakes when I was waiting for my car, as if he knew something I wasn't aware of.

BTW, do you recall what the nature of the problem is and the "fix" in the original Cali that you mention?

 

When I first purchased my California, I sometimes had squealing brakes. I asked my dealer about it, and they replaced the pads with ones that were "softer" which solved the problem. I didn't ask for specifics of what "softer" meant.

 

My Cali was an early 2010. The fix was to change the pads. But the squeak still persisted.

 

The bedding in procedure from Ferrari in my 2010 Cali was multiple stops with very heavy brake pressure, with a short cooling period then followed by more multiple stops from higher speeds, with a short cooling period, followed by stops from 80 MPH or so and VERY hard, like into the ABS. The brakes will take it.

Anyone that has brake squeal has a simple fix. this will bring big smiles to you! Take the car up to 70 mph or more then STAND ON THE FLIPPING BRAKES FOR A CHANGE, getting into ABS and ENJOY THE RIDE.

You may have to do that twice but the squeal will go away! And your brakes will survive. And your body will get a nice shot of adrenalin, hopefully it survives.

This works guys. Now, my 2012 doesn't seem to have squeaked much if at all and my FF never has but I drive both like I stole them. I did wear out a set of REAR pads in about 32,000 miles while the fronts are still very good. The rears may have worn from the traction control stopping wheel slip in the rears on a regular basis .

Baby your stupid Prius, drive your Ferrari.

Rick

 

Sounds like Ferrari finally fixed things for Cali 30 owners, with new pads for front and rear.

Too bad they didn't contact and fix things for the guys who bought the early cars.

(And yeah I did the whole bedding thing multiple times--got the speed up to 85 and stood on the brakes triggering the ABS.)

 

I am not familiar with the alignment of brake pads on our cars but I do know something about brakes on racing bikes (the kind that runs on leg power). Those bikes can reach 50-60 mph on the pro circuits so they are not trivial.

If I draw experience from cycling, brake pads are normally slightly toed-in towards the forward edge with respect to the direction of travel of the braking surface (a car's brake rotor). This allows the pad to be (gradually) drawn onto the (rotor) as the wheel assembly rolls forward, contacting the front part of the pad first. Using a good quality brake pad this eliminates brake (shoe) vibration that cause squeal and chatter. Whereas if the pads are completely parallel to the (rotor) the pads will chatter and/or squeal like crazy (because both the front and rear edges of the pads are catching the braking surface in alternating fashion).

A softer pad will accommodate toe-in because while a very rigid and overly hard (i.e. poor quality) pad may still vibrate if it is not fastened solidly enough to the calipers, the softer pad will bend or compress slightly instead when pushed into the brake surface and dampen the tendency to vibrate. In cycling, the trick is to make pads that behave like they are soft but still wear slowly.

In the case of a CCM brake, a softer pad will help you bed the brakes better and without vibrating (using abrasive friction). Once the brakes are bedded, the softness of the pad no longer matters because braking action will come mainly from cohesive friction. At that point, the pads and the rotor surfaces are perfectly matched and won't squeal.

 

Only temporarily for my car. Then the squeaking returned. I even experimented with rinsing the discs with some slightly soapy water. Same effect, it helped for a while then the noise returned.

 

8 out of 10 times, it's proven to be brake dust build up. As you noted, washing the brake dust out of the caliper/pad area " fixes " it until you have driven long enough to build it up again.

I'd ask if you use any chemicals when you wash your wheels, soaps, or wheel shine after you're done. If you do, don't. If you have to , to clean the wheel, spend the extra time to make sure you clean away any residue. These act as dust magnets.

Brake pad alignment / brake pad shims / tapering the pad material / etc are things done to fix the 2 out of 10 that are not fixed by keeping the area clean.

Last question, are they OEM brake pads?

Come by sometime, we can take a look with you, come by when it's happening, not after you cleaned them up though... LoL

S

 

I'm curious to know how bad is the squeal. Iow, is it just annoying squeal that you hear occasionally (but driving you crazy) or is it loud and occurs every time you brake?

I'm asking bc I too hear a squeal from my Cali but it seems not to be often, it's not that loud and it does stop when I press a bit harder. I am thinking not to worry about it...

Otoh, I had a pre-owned 911 turbo that had I don't know what kind of brakes. The squeal was so loud you could hear me coming a 1/4 mile away. Embarrassing and the squeal increased as I slowed! (mechanic told me they were competition pads and there was nothing otherwise wrong). I eventually caved and changed the pads. Is this the type of squeal you are talking about?