When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
In another thread I have discussed a rattle the source of which has been evading me for nearly a year. I believe that today my independent mechanic finally found it. My car is a 2008 C4S with PCCBs and 63K miles. The rattle is in the front right suspension but even though I've used Chassis Ears (thanks Bruce for the suggestion) I have not been able to find the culprit. After driving it first alone, then with another mechanic in the car, he concluded that it is the brake pads rattling around in the caliper. The key symptom he found is that while driving on a bumpy road, the rattle stops immediately when the brakes are lightly touched - something that I had never noticed. He advised me to pull the pads and replace the anti-vibration dampers that hold the pads to the pistons. Note that the carbon-ceramic rotor is in perfect condition so there is no damage from the loose pads.
I went right home and pulled the wheel and carefully removed the pads. The pad spring clip and retention pin were in good condition. Unlike in my previous 997.1 S with conventional brakes, these pads did not have dampers adhered to the back of the pads and clipped into the pistons. Also, it looks like the PCCB calipers have white ceramic pistons which was a surprise to me. The pads seem to be the original factory units: Pagid P40-3 FF. Below are photos.
So my questions are:
Is it normal that there are no anti-vibration dampers behind PCCB brake pads?
Is it normal for PCCB calipers to have ceramic pistons?
Has anybody experienced their brake pads rattling around in the caliper and if so, what did you do to cure it?
Suggestions on how I should proceed to fix this?
THANK YOU in advance for any info or insight that you can provide.
Regards,
Scott
Pad P/N Friction surfaces looks healthy Back side. Clean where pistons touched pad but no dampers. Healthy looking PCCB rotor. Pistons but no dampers Inboard pistons
It's been a lot of years (9 actually) since I've had my 997.1 PCCBs apart but from memory, those caliper pistons look different than mine and I used the pronged, adhesive vibration dampers when installing mine. Maybe it's because mine is an 05 that was essentially a carryover of the 996TT PCCBs (350mm at all 4 corners).
It's been a lot of years (9 actually) since I've had my 997.1 PCCBs apart but from memory, those caliper pistons look different than mine and I used the pronged, adhesive vibration dampers when installing mine. Maybe it's because mine is an 05 that was essentially a carryover of the 996TT PCCBs (350mm at all 4 corners).
Good information Pete. Thank you very much. I think that I will call Suncoast Porsche and see what official dealership information indicates.
Okay. So I called Suncoast Porsche and talked to their parts department. Based on the VIN of my car, it has factory PCCB (which I knew). Per the PET it should not have anti-vibration dampers between the pads and the caliper pistons. Hmmm. Also, the parts guy could not confirm or deny whether ceramic pistons are standard in PCCB calipers.
The thought has occurred to me that maybe if I bend the spring clip to bend down further it will put more pressure on the brake pads and keep them from rattling. I'll give this a try unless somebody has a better idea or a reason that I should not try it.
I also ordered replacement spring clips and retaining pins but they won't arrive until next week.
Last edited by campbesl; 08-10-2022 at 03:55 PM.
Reason: Improvement
I would put some of the anti-vibration paste on the back side of the pads too. I use itnto adhere the caliper pistons to the pads so apply it then install as quickly as possible and press the brake pedal to seat the pistons against the pads. Have to do only one wheel at a time when using this method as you can't press the pedal with a caliper disconnected or without pads in it.
I would put some of the anti-vibration paste on the back side of the pads too. I use itnto adhere the caliper pistons to the pads so apply it then install as quickly as possible and press the brake pedal to seat the pistons against the pads. Have to do only one wheel at a time when using this method as you can't press the pedal with a caliper disconnected or without pads in it.
SUCCESS!!! While waiting on Pelican to deliver the spring clip and retaining pin kit, I went ahead and bent my existing spring clip to put more force on the pads. I really had to press it down to get the alignment pin through. I put it back together and went for a drive and wow was it nice to have that rattle go away.
Pete - I ordered some CRC Disc Brake Quite to do as you suggest but for now all is good. I will go back and put some on to make sure that the pads don't ride against the caliper when not braking.
The disc brake quiet goes on the back of the pad to prevent a harmonic resonance against the caliper pistons which is what makes brakes squeal....maybe that's what you meant by "caliper".