BatmobileWS6

I have ceramic brake pads on an otherwise stock brake setup, for now. Pretty much everytime I come to a stop it squeaks. A friend told me that it is because the pads were ment for aftermarket rotors? Could that be true?

trackbird

iTrader: (4)

Probably not. Rotors are all made of similar grades of iron. There can be some differences, but they are typically minimal. It's probably more of an issue of the friction level of the new pad and the amount of pressure it takes to stop the car. Meaning, a really aggressive pad may require very light pressure to stop the car. Since it's only lightly running against the rotor, it could be more prone to chatter/vibrate or squeak. Changing to a different pad compound may be enough, or you could try putting a small amount of disk brake caliper lube on the backing plate where it contacts the caliper. Just use a small amount, you don't want it getting hot and winding up on your rotors. That will allow the pad to "float" in the caliper and in some cases can reduce or eliminate squeaking. It's cheap and easy, so it's worth a try.

I have a set of Hawk HP+ pads and I'm running a 6 piston wilwood based kit. Those pads are obnoxious on my car. It's a piercing noise that's shockingly loud. Almost any other pad has been fine. It's just a specific combination of pressure and resonant frequency (of the brake parts) that results in a squeal/squeak in most cases.

BatmobileWS6

Yeah i'll try that...mines not that loud but is becoming very annoying.
So is there certain types of pads to be used with certain rotors? Is there any problems with the specific combination of pressure and resonant frequency that your talking about?
By spring time I plan to invest in drilled and sloted rotors, so hopefully the combination will work well with the ceramic pads I have.

trackbird

iTrader: (4)

Drilled and slotted are not an upgrade (already covered in about 100 threads here), so unless you want the look, I'd pass on them. They will typically be made of similar iron to your stock rotors and they will probably squeak too. The resonance is based on the caliper weight, bracket strength (that holds the caliper), rotor diameter and rotational speed, pad pressure, etc. Most of the money spent by manufacturers on brake development is spent looking for a quiet friction material that doesn't excite any of the harmonic vibrations that can make noise. So, to keep them quiet, they test many, many pad compounds until they find one they like that won't offend the owners of the vehicle.

There really aren't certain pads for certain rotors (unless you get into the Carbon/Carbon brakes on some Porsche cars and used in Formula 1 racing), you just have to find what works and is quiet enough to live with for your tastes.

Hope that helps.

BatmobileWS6

Yeah it does, thanks.
So if drilled and slotted rotors is not a upgrade, there really is no point then?

trackbird

iTrader: (4)

Not with todays pad compounds. In the old days, pads had issues with producing gasses as the resins they used in the pads cured under the heat of racing. Modern resins are so good, it's just not an issue these days. So, yes, they were for race cars of the time, but it's not needed these days. A quick search here will get you more info than you care to read on the subject.

DJ_951

Did you use synthetic brake lub on the pins? I would make sure your brakes are floating on the pins.

did you buy a performance pad or race pad. race pad will make noise

The drilled rotors are kind of fun after you paint the caliper, "are those bremo's"

BatmobileWS6

Yeah i'll search more about it, just havn't got a chance to read into it yet.
I just bought the car within 1K miles ago...and the prevous owner had it done at a brake shop. The receipt says the pads are sets of CMX749 AND PD750 ceramic pads. The description says:
"Machine and reinstall front and rear disc rotors. Install new front and rear ceramic pads, shims and hardware. Clean and lube hubs and brake assembally. Add brake fluid. Road test."
Yeah the calipers are already painted...so I would like how the rotors would look behind some new wheels im getting.

DJ_951

Good....problem being they crack, will probably not last 50k like stock. Did it anyway.

I would make sure the rims were torqued down properly (and evenly) and relube the pins. There are a lot of places that can't seem to do either. A local dealership couldn't do either on my mom's Yukon. Was a easy Mother's day gift fixing them though.

DJ_951

oh, enjoy the new car.