Brake squeal and PFC carbon Metallic pads - any help?
Discussion
Put the OEM pads back in. If PFC guarantee no squeal without any knowledge of the application or the disc design then they’re insane.
If you follow the bedding procedure they should have given you they might quieten down for a while but it will come back
ETA - here you go
https://www.gb-ent.com/pages/performance-friction-...
If you follow the bedding procedure they should have given you they might quieten down for a while but it will come back
ETA - here you go
https://www.gb-ent.com/pages/performance-friction-...
Edited by The Wookie on Monday 22 April 20:05
That's really disapointing as PFC make great products. I assume they are the Z rated entry level pads Julian? I have used them successfully and bedding in was easy so perhaps the discs had a bit of oil or grease on them? I would try and emery cloth both the discs and pads to start from scratch just in case there was irregular deposit of pads.
I have no experience with those pads, but things that have helped with brake squeal on other cars have been chamfering the edges of the pads, adding anti-squeal shims between the pads and pistons, or removing anti-squeal shims if present. Sometimes a good clean of the caliper helps - sometimes it makes it worse. It seems to be a matter of just changing things that affect the natural frequency until the resonance goes away.
Many thanks gents. The pads and discs were meticulously clean upon install and the calipers were physically removed from the car and cleaned up.
I’m not sure what pads I have, Nick, but I’ll check the invoice and revert that information. Would it make a difference? (presuming you’re thinking about compound)
Can definitely chamfer the pads if you think that’ll help? Bit of a faff but up for it if it has a good chance - how much chamfer? 4mm leading edge?
I’m not sure what pads I have, Nick, but I’ll check the invoice and revert that information. Would it make a difference? (presuming you’re thinking about compound)
Can definitely chamfer the pads if you think that’ll help? Bit of a faff but up for it if it has a good chance - how much chamfer? 4mm leading edge?
Chances are the 986 is prone to squeal and the OEM setup has been carefully tuned to prevent it.
As GreenV8S says things like chamfering and squeal shim tuning can improve it (although rarely actually completely cure it by itself in my experience), sometimes adding high temperature dampening grease (Eg daikalub NOT copper slip) to things like abutment faces or pad retention pins but it’s a trial and error process depending on the car.
In my experience of solving brake noise issues really the only way to fix it properly without a change of pad compound is a proper analysis and either tweaking things like the disc design or adding mass dampers to the pads, bracket or caliper.
As GreenV8S says things like chamfering and squeal shim tuning can improve it (although rarely actually completely cure it by itself in my experience), sometimes adding high temperature dampening grease (Eg daikalub NOT copper slip) to things like abutment faces or pad retention pins but it’s a trial and error process depending on the car.
In my experience of solving brake noise issues really the only way to fix it properly without a change of pad compound is a proper analysis and either tweaking things like the disc design or adding mass dampers to the pads, bracket or caliper.
Edited by The Wookie on Tuesday 23 April 07:08
Reporting back.
I disassembled everything, cleaned it all and hit the friction surfaces with a touch of emery cloth.
The squeal came back within 5 miles.
It’s horrific.
So I dug out my invoice - seems that I have “08” pads - which seems to mean that they are actually not road pads!
Which explains that I can’t get anywhere near enough heat into them on the road to shut them up.
Not sure whether to keep them or move them on.
I disassembled everything, cleaned it all and hit the friction surfaces with a touch of emery cloth.
The squeal came back within 5 miles.
It’s horrific.
So I dug out my invoice - seems that I have “08” pads - which seems to mean that they are actually not road pads!
Which explains that I can’t get anywhere near enough heat into them on the road to shut them up.
Not sure whether to keep them or move them on.
Julian Thompson said:
Reporting back.
I disassembled everything, cleaned it all and hit the friction surfaces with a touch of emery cloth.
The squeal came back within 5 miles.
It’s horrific.
So I dug out my invoice - seems that I have “08” pads - which seems to mean that they are actually not road pads!
Which explains that I can’t get anywhere near enough heat into them on the road to shut them up.
Not sure whether to keep them or move them on.
Not surprised as the Z rated pad, which I thought you had, is very silent, and much cheaper. 08 is a brilliant compound but not for the road, you'll get decent money for it on ebay. I disassembled everything, cleaned it all and hit the friction surfaces with a touch of emery cloth.
The squeal came back within 5 miles.
It’s horrific.
So I dug out my invoice - seems that I have “08” pads - which seems to mean that they are actually not road pads!
Which explains that I can’t get anywhere near enough heat into them on the road to shut them up.
Not sure whether to keep them or move them on.
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