Brake Squeak

[XCITsNU]

JMatt,

Mine has the same problem on the right front side too.

[DZeckhausen]

Originally Posted by JMatt

I followed the directions exactly this morning in my 911. I was braking and accelerating so hard in between that on about the 8th time I thought I was going to throw up from motion sickness. (Seriously - for some reason high deceleration makes me sick).

Then you might have the wrong car! The Porsche 911 has about the best braking performance of any road car and it's not just due to the Brembo-made 4-piston calipers and large rotors at all four corners. The rear weight bias allows the rear brakes to do a greater percentage of the overall work, thus resulting in much better braking performance than a nose-heavy sedan. Slap on a set of racing tires on your 911 and there's no way you'll be able to keep lunch down when threshold braking!

Got to work and pulled up to the gate at the garage to swipe my pass - no squeal. None. The question that remains, is how long will this last before they start sqealing again? One day? Week? Month?

That depends on the type of pads you are running in your car and on your driving style. If you brake late and aggressively, you will tend to refresh the transfer layer and keep the pads quiet for a very long time. If you drive very conservatively, then the low-temperature abrasive nature of your pads will result in the transfer layer being removed over time and your squeak will come back. It can be cured, however, by another bedding session.

Some pads are very abrasive by nature and tend to become unbedded quickly. At the extreme, are racing pads such as Hawk Blue, Pagid Orange, or Performance Friction 01 which will unbed themselves on the street within an hour. These racing pads have no adherent component to their friction until they reach racing temperatures. Other pads, such as the Textar street pads that came standard on your Porsche, are pretty good at maintaining a transfer layer on the rotors under street driving conditions.

[JMatt]

Oh, its the right car allright!

I wasn't kidding though. The thing brakes soooo hard, that I can literally make myself nauseous. The braking distance from 100 to 0 is amazing. But doing 0-60-0 10 times in about 90 seconds will make you hurl.

BTW: Drove the 911 to work again today. No squeal.

[srt42]

Well, I finally had a chance to try the bedding procedure again (I'm still fighting nausea) and with the 2 added runs from 80-10, I believe I got it. I have not heard a squeak in 2 days and it is music to the ears. Hopefully, it's gone forever!

It was not fun though. I got a wild hair up my butt, due to I'm sick of the squealing and decided to go to my selected piece of road to give this a try which is about 40 miles away. As I'm driving there (During rush hour), it starts raining. Not good. So I give it 2 attempts, tires spinning on the wet pavement and all and both were nixed due to halfway thru the procedure, traffic came up behind me. So, I finally say "screw it" and I drive towards home. I was not too happy that I went to all this effort and I was going home without my brakes bedded, so I decided to take one more try on a side road and if I was lucky, no traffic would get in the way. Well, on my first attempt, everything looked great and then some stinking truck pulls off a sideroad and comes up behind me which ruined that run. Man, am I getting pissed. So, I yank the car around and give it one more try going back towards the highway and I finally accomplished the task. It is not a small task finding the right place to do this procedure.

Thanks Dave for your wonderful insight and tips. I believe my problem is solved.

[DZeckhausen]

Originally Posted by srt42

Well, I finally had a chance to try the bedding procedure again (I'm still fighting nausea) and with the 2 added runs from 80-10, I believe I got it. I have not heard a squeak in 2 days and it is music to the ears. Hopefully, it's gone forever!

It was not fun though. I got a wild hair up my butt, due to I'm sick of the squealing and decided to go to my selected piece of road to give this a try which is about 40 miles away. As I'm driving there (During rush hour), it starts raining. Not good. So I give it 2 attempts, tires spinning on the wet pavement and all and both were nixed due to halfway thru the procedure, traffic came up behind me. So, I finally say "screw it" and I drive towards home. I was not too happy that I went to all this effort and I was going home without my brakes bedded, so I decided to take one more try on a side road and if I was lucky, no traffic would get in the way. Well, on my first attempt, everything looked great and then some stinking truck pulls off a sideroad and comes up behind me which ruined that run. Man, am I getting pissed. So, I yank the car around and give it one more try going back towards the highway and I finally accomplished the task. It is not a small task finding the right place to do this procedure.

Thanks Dave for your wonderful insight and tips. I believe my problem is solved.

I hope you're right, but I wouldn't hold my breath. If my assumption about the stock SRT8 pads is true, they've installed a rather agressive track pad in there. As such, it is abrasive when cold and will wear away that nice transfer layer you just put down in short order. It's not until a track pad gets up to 300 or 400 degrees that the adherent mode friction kicks in and you can sustain the transfer layer. Street pads are designed to run with a mix of abrasive and adherent friction right from the first stop. So you can bed in street pads and they will stay bedded in for a long time. Track pads will unbed themselves when driven "cold" on the street.

It's that very property that allows you to use track pads as a tool to remove unwanted rotor deposits. See: http://www.zeckhausen.com/avoiding_brake_judder.htm

I'll keep my fingers crossed that you've solved the problem.

[srt42]

If these are truly the wrong pads for a street car that will constantly have problems, what should we all do, wait for after-market pads to become available or make numerous trips to the dealership to see if they can resolve it? Obviously, none of us wants to do the latter and until somebody reports that DCX has an answer for the problem, taking it to the dealership would be non-productive except to document the problem.

To answer my own question, if I have any other problems with the brakes, I will definitely take it to the dealership and report the problem which is everyone's duty to make them address the problem.

[vvv90]

DZeckhausen....I love your posts. Keep 'em coming! I'm learning a lot about brakes from ya.

Also, did you ever find a volunteer vehicle to mock up some ceramics for us? If you don't find anyone by winter, I'm tempted to pull my calipers off and ship them to you.

[DZeckhausen]

Originally Posted by vvv90

Also, did you ever find a volunteer vehicle to mock up some ceramics for us? If you don't find anyone by winter, I'm tempted to pull my calipers off and ship them to you.

We did have someone stop by the Torrance StopTech facility to have their car measured for a big brake kit. That's when they pulled the pads and learned that they were a new, obscure shape. They (and I) do not have the ability to create pads for this platform. That's going to have to be up to the large pad manufacturers like Hawk, Performance Friction, Bendix-Mintex, Pagid, etc. As soon as anything becomes available, I'll let you know.

For the "cost is no object" crowd, there will be a StopTech 4-wheel big brake upgrade soon for the SRT8, using their new 6-piston calipers. The standard street pad for that kit will be the Hawk Performance Ceramic pad. So if you want a sledge hammer solution to the brake dust problem, that will be it!

[vvv90]

Originally Posted by DZeckhausen

We did have someone stop by the Torrance StopTech facility to have their car measured for a big brake kit. That's when they pulled the pads and learned that they were a new, obscure shape. They (and I) do not have the ability to create pads for this platform. That's going to have to be up to the large pad manufacturers like Hawk, Performance Friction, Bendix-Mintex, Pagid, etc. As soon as anything becomes available, I'll let you know.

For the "cost is no object" crowd, there will be a StopTech 4-wheel big brake upgrade soon for the SRT8, using their new 6-piston calipers. The standard street pad for that kit will be the Hawk Performance Ceramic pad. So if you want a sledge hammer solution to the brake dust problem, that will be it!

Ouch! For what I'm guessing will be a $3,500 brake upgrade, you can replace the rotors and pads quite a few times before you hit that number. I'll wait for the pads.

Of course, for any seriously boosted or track car, the stopping for for those 6 piston monoblock brakes has got to be insane!

[taylormotorsports]

Though my car is not an SRT, I just got back from following the bedding process and it worked like a champ!!!