CSK 911 C4S

When I pulled over my 1st thought was I just broke a control arm and the suspension was just scraping against the wheel.

A few back and forths the stone luckily popped out.

Porscheforever

You can't, but no need though. When you spray the serum on the early steps that I suggested, target the little drilled holes too as dust and rust like to build up on that areas. The chemical will sip and drip from the holes to bottom on either sides of the rotor due to gravity. So make sure to spray plenty on the top holes or just spray plenty to the top of the rotors.

Also, use blower after washing to prevent the serum on the back side of the rotors dripping continuously as you can't really wipe them off with normal effort.

For the wiping of the rotors with hyde serum on last steps, you only need to wipe the front side.

If you loosen / tighten the sprayer head, you can target the drilled holes better. I recommend using standard round sprayer because I think stock hyde bottle has a fixed square sprayer.

dkuznetsov

No offense, but you and your suggestions are idiotic. You say its normal, then you say you have never heard your brakes on the street. I tried to bed them, and no avail. I drive the car hard, and I brake hard but this level of brake squeal is not normal. Interestingly enough the brakes aren't audible under soft braking. I guess I'll find out tomorrow, this isn't my first high performance car, I had a BMW m4 with carbon ceramic brakes and they didn't sound like this.

STG

Don't go crazy with any tire dressing.

Just use a light coat of Aerospace 303 wiped on with a sponge or another brand that doesn't sling.

Cheapo spray on tire dressing that over sprays all over the rotors and gets all over when driving isn't good. A lot of your car wash places and dealers also use this junk.

Could be a contributing factor?? A slick of this stuff on the pads and rotors can cause issues. Have heard of it before.

bogdan_p

Mine squeal sometimes under light pressure coming to a traffic light. I usually try to prolong my braking for maximum noise when it happens, you know, to annoy the people busy talking on their phones.

Some heavier stops might help for a while, might not. I'd say it's just the compound of the pads.

Interestingly, previous cars (M3, Z06, Viper) with steel brakes were mostly whisper quiet on the stock compound, but their pads were also complete crap on the track after 2 laps. I wonder if these stock pads will fare any better..

also, OP... steel brakes =/= carbon brakes

BLK991CAB

OP: How many miles are on the car? Did you buy it used? Was it tracked? Was the car sitting for a while? Bite the bullet and get new rotors and pads!

My R8 brakes squealed the loudest when I first got the car (it was used 19K on it at the time) . It was embarrassing pulling up to stop lights and sounded like an 18 wheel truck. Turns out, the previous owner had track pads on the car (pagid yellows). I put new rotors and pads on the front and never heard a sound again.

Does it sound like this:

Connor Flynt

Mine sounds like this. It's maddening. Anything I can do to make it stop?

Jasonpdx

Pep!RRRR

Noah Fect

Yeah, that video is insanely stupid. Ask your dealer why Porsche is the only performance-car manufacturer on the planet who felt the need to produce something like that.

drcollie

Brake Squeal is caused by ultra high-speed vibrations as the pads contact the rotors. Simple as that. <<< Read that again and remember it.

Everything anyone does, whether it be brake sticky goop, spring shims, re-surfacing, driving it hard to break down the glaze etc., is done to minimize those vibrations. Now that you know what causes it, how to do you stop it?

You have to understand that a braking system generates heat, and a lot of it. So manufacturers take into account how the vehicle is going to be used when spec'ing out materials and tolerances. A luxury street car is not going to see track duty, so the goal there is decent stopping power, progressive feel, and quiet. A car like a Porsche must stop fast because its a true sports car so quiet is less an issue, and allowance for more heat generation must be made as well as more aggressive pads for performance.

The caliper is held in a bracket and the pads float in that caliper bracket. They have metal backing plates that have to move back and forth in the bracket. When metal gets hot, what does it do? It expands, therefore the pad MUST fit looser in the caliper bracket which means tolerances are greater on a track oriented car than on a street car - those Lexus brakes are not going to ever get hot. You can't have the pads seize in the bracket when they get red hot, so the build more room in the space to allow for expansion. That space allows the pad to vibrate against the rotor when everything is cold and that equals squeal. The spring shims on the back of the pad are a way to try to compromise and put pressure on the bat to the rotor. Make sense? That is also why dedicated track pads squeal like a stuck pig - they are loose in the brackets because the maker KNOWS they are going to expand when they get hot. Ever notice how track pads are only noisy when they are cold? The metal backers haven't heated up yet.

There can also be a glaze build up on the rotor, this is why sometimes hard driving and repeated high speed stops will clear off the glaze, but that doesn't always work.

If it really, really bothers you - then the best solution is to replace the rotors with factory new, and the pads with OEM Porsche as well. That gives you a fresh mating surface that is OEM and believe me that Porsche AG has spend thousands of hours trying to find the perfect balance between quieter brakes and performance. All the rest of the solutions are just snake oil. And you still may get some squeal even then.