DWS964

At the last DE (Road America) I switched to Pagid Orange pads up front, and "found" a lot more braking. Wuhoo. I kept the pads in for the drive home and drove on the street for a week or so. The squeal was OK for a while, then unbearable. Seemed it was on only the LF. I dropped in a used set of Hawk HP, did not use the mushrooms, and the squeal was unchanged. I ordered a set of MetalMasters from Pelican. They have the backing for "no squeal"., Bedded them in and were better. (put in front and rear) But now I still get the same, really bad, squeal whenever the brakes get a bit hot from a dose or two of heavy brake. I have not tried using the mushrooms, yet, as I want to be able to easily swap in the Oranges for the DE next weekend.
Ideas? Do I need to resurface the rotors? Clean up the guide plates? use the mushrooms? It seems that it is only the LF (maybe the LR)

ducnine

I had new pads put in a year ago and the mechanic said they might squeal. Holy crap was there squealing. My wife did not want to ride with me anymore. I took it to Mid Ohio for a DE last year and I thought that would help....but no dice.

I took it to a Porsche Club clinic earlier this year and the mechanic suggested 2 thing he does for brake squeal.

*The first thing he does is to go find a uninhabited road and go in reverse at maybe 10mph and slam the brakes. Do this two or three times and it could help. I did not believe it until he did it and the squeal went away.
*The second thing he suggested is to take the pads out and chamfer the ends. This could be a more effective solution.

Well I tried the the reverse trick myself and it did help albeit temporarily. So I took the pads out and Chamfered it. This worked better. And after doing a DE a few weeks ago with some Heavy Breaking, I think this did the trick, cause it only squeals now when its been the car has been sitting for a few days. Once on the road the squeal goes away.

Therefore my suggestion is give the chamfering a try and then probably need some heavy breaking to get them all set and squeal should be gone for the most part.

Good Luck.

DWS964

Thanks
I went back and read a bunch of posts in the Search on brake squeal - but slamming on the brakes in reverse is a new trick.
I will clean everything up, better this time, try some hi-temp grease on the sliding points and some CRC squeal stop on the back of the pads.

scott 964

try this...on mine it was not the breaks where the squeek came from but from the very rusted heat shield behind the disks on the front wheels...£15 each for new ones and once fitted no squeeks..

DWS964

Update - changed pads last night (installed used set of Hawk HP from other C4 that have about 70% left), cleaned everything with CRC Brakekleen, cleaned up the guide plates. Noted that on rear calipers the pads were really tight - hard to remove/install. Front pads - any/all of them - drop in easily with lots of clearance. I filed the ends of the rear pads to allow them to drop in and move around a bit. Used hi-temp grease on the sliding surfaces, and CRC orange goop to stop squeal on the back of all pads. I used the mushrooms on the front pads, but did not have any for rear pads.
It was late and dark, so I did not do a full bedding in, but enough to get the brakes fairly hot. Once hot, the brakes squealed again under hard braking. This seems different than other folks who squeal at light application and goes away under heavy brake. Braking is smooth, with no vibration. It seems to be independent of the pads.
Possibilities:
- How tight should the pads be inside the calipers? I assume my rear calipers have some build up of corrosion/dust behind the guide plates, causing the pads to be tight. Tight or Loose? Any problem with grinding off a bit of the backing plate on the pads? I noticed that one of the old rear pads installed by the PO had been ground off a lot, and was a very loose fit in the caliper.
- Do I need to resurface the rotors, after using the Pagid Oranges on the fronts. This is when it all started.
- Bedding in. I have read to bed in new pads on used rotors, and new rotors with used pads.
I am running a DE at Putnam Park on Saturday. I am planning to start out with the Hawk HP pads, and then possibly switch to the Pagid Orange

Thanks for the help and advice.