atb

If your rotors are drilled, the vanes will pack with brake dust. Have you tried removing the rotors and blowing them out? (Don't do in an enclosed area)

Murray

When I take everything apart tonight I will do that too. At this point I am willing to try anything.

mirousse

I had the same problem. Bought high quality brake pads + damper. Problem still present, squealed like a locomotive! Went to Napa auto parts. They sold me EBC "organic" pads (I guess non-metallic). Amazing results. Never squeal, reasonnable on dust, brake just fine. I'm 2 years into them and the wear is ok. Around 40$ CDN.

Michel

89 S4 - Daily driver

Murray

Squealed like a Freight Train describes my situation exactly. If all else fails I may try that. There is a Napa close by.

Thx

928 at last

Mine were squealing before the refresh this past spring. New Hawk Semi Ceramic pads, the Porsche dampers, and the Zimmerman Rotors. Bedded them in per the Tech Bulletin, (Did it on a quiet backroad - Properly).

Very little dust and dead quiet since.

the flyin' scotsman

I used the Colin method of 100 to 10 kph repeated 3-5 times on deserted hwys............beds the pads and rotors with no squeeks after cleaning and champhering.

if any noise returns just repeat.......it works well.

Jim M.

Brake squeal, any brake squeal, all brake squeal is caused by vibration of the pads. Not using the brake pads as Porsche designed is bypassing one of the steps the factory designed to prevent this problem. Your 1st step should be to follow the maintenance manual and install the anti-vibration pads and the factory break in process. After that all of the steps outlined above will help the pads bed in and avoid brake squeal. Skipping factory recomendations is bypassing what has been proven to work.

Bill Ball

Although I agree with Jim's suggestion that you should install the antivibration pads if simple measures fail, I can't say the antivibration pads are a cure-all. I've been in 928s that squealed with them installed, and then there's my car that hasn't had them for at least 9 years without any significant squealing. It could be the semi-metallic pads as well, but I run the same ones as the OP without a problem. Who knows, it could be the rotors. Mine are Zimmerman drilled and sold by Design Rotor Technology on eBay. I feel the need to give them a little plug. I don't know what they did to the rotors but mine were installed 80K miles ago in late 2006, and they are not even half way to the spec limit. They weren't cryo'd as far as I know. The earlier Porsche fronts I had been using lasted about 40-50K miles before they hit the 2mm wear limit.

NoVector

To the OP, does rinsing the dust off the rotors when you wash your car make it any better? Even for a while??

dcrasta

Clean everything (Brake-cleaner)
Use anti-squeal on the backs of the front pads (you're missing dampers so thats part of it).
If you really get annoyed by squealing switch to organic pads (on the rear only.. I hate organics on the front, I dont think they stop well enough).
Check for sticking calipers.

Murray

I have ordered a set of dampers for the rears and will pick them up at SITM. Maybe I can get them installed on Friday before too much beer has flowed.

dcrasta

After the brakes are cool enough to touch you should be able to get it done in less than 30 minutes (including time to jack the rear up and remove the wheels.).

928 at last

I've found that using the factory pads results in almost daily dust removal duties. That's why I went with the semi ceramics. Hat's off to Roger for the recommendation!

Jim M.

The factory pads are Textars and yes, they do make a lot of dust. They were chosen because they last, stopping is adequate (not great) and with the correct installation don't squeal. Everything a manufacturer wants for the "average" owner.

dr bob

My too sense:

The pads need to fit between the steel plates without clearance but without friction. A zero-interference fit is what you are after. Loose and they vibrate (Noisy rumble or squeel), tight and they won't retract correctly and end up glazing over and squeeling. "Normal" cars don't come with the little damper things, and they really aren't dampers on our cars anyway. "Normal" car need something to dampen vibration, and the easist way is to add something betwen the pad and the piston. Permatex has a blue goo that does the trick, but it doesn't pull the pads clear of the rotor as the factory pieces do on our 4-piston calipers. Remember that the pistons ride in square-section seals, so the piston rolls the seal slightly as it extends. The slightly-rolled seal then retracts slightly when pressure is relaxed. Attaching the pad to the pistons with the factory pieces causes the pad to come clear of the rotor slightly when pressure is removed. No contact means no vibration, cooler pads, and no glazing.

Recommendation: Pull the pads and wash the caliper, pads and rotor with soap and water to get as much dust out as possible. Don't be shy with water pressure from the hose to clear as much dust out as you can from the inside areas of the calipers. Scrub the pads with a wire brush and that same detergent and hot water to get all the imbedded dust out of the faces, and to clean the back for a good bond with the "dampers". Next, test-fit the pads in the caliper frames with the pistons retracted. Do they "just fit" between the end plates? A little adjustment with a file is OK if they are too tight, but go slowly and gently of you need to do this since there's no good way to add metal back if the pads end up too small. I use a smear of waterproof grease, like caliper slide grease in the tube, on those end plates once the pad fit is confirmed. Then snap the factory "damper" pads into thepistons, remove the adhesive protection film, drop the new pads in, and gently apply the brakes to set the adhesive pads on the back of the brake pads. After the pads are seated this way, there should be a very small clearance between the friction face of the pad and the rotor face. You (hopefully) won't be able to wiggle the pads at all, but should be able to see or maybe feeler-gauge the clearance. Turning the rotor should make almost no noise at all from pad friction.

Lots of noisy-brakes problems can be solved with thorough cleanig with detergent and water. Brake Cleaner is great for getting greasy deposits and fingerprints off of friction surfaces, but it's dangerous to humans and honstly doesn't do nearly as well at flushing non-greasy brake dust from brake parts. For sure the detergent is better for de-crudding brake pads.

Then follow the pad manufacturer's recommendations for bedding the pads. Recommendations vary depending on type of pad, from the factory method for their organic pads to the more severe methods needed to bed more aggressive pads.

My gentle driving and failure to slow for turns netted me 60k on a set of MetalMasters, and they were worn just to the point where the wear sensors wre starting to get too close to the rotors. Rears look almost new. They are OK for street driving, relatively low dust, and low noise. WheneverI started to hear them, a thorough wash and re-lube would take care of them. Remember that the brake dust can be corrosive to the aluminum calipers, so it's a good idea to regularly get it all out. Cleaning coincides with annual fluid replacement and brake inspection. Handy time for a wheelwell inspection and detail too while the hose and detergent are out and the wheels are off.