Squeakiest brakes in the world
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I have had VERY noisy brakes for some time. I had the garage install anti-squeal shims - no improvement.
So, bough toools etc and this week I:
filed edges of the bads - no change
removed anti-squeal shims - no change
coated back of pads with coppaslip - no change.
The problem is definiely the rear brakes - I know this is I did the rears only 2 days ago & the squeal stopped for about 30 miles of driving - but it is back with a vengeance!
The rear discs were replace when I bough the car, 10k miles ago. The rear pads exhibit hardly any wear at all, and the fronts still have 5-6 mm of pad at least.
I am at the end of my tether - any suggestions???????????????
So, bough toools etc and this week I:
filed edges of the bads - no change
removed anti-squeal shims - no change
coated back of pads with coppaslip - no change.
The problem is definiely the rear brakes - I know this is I did the rears only 2 days ago & the squeal stopped for about 30 miles of driving - but it is back with a vengeance!
The rear discs were replace when I bough the car, 10k miles ago. The rear pads exhibit hardly any wear at all, and the fronts still have 5-6 mm of pad at least.
I am at the end of my tether - any suggestions???????????????
#2
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What pads do you have in there? Have you considered switching pads, perhaps to low dust/low noise Metalmasters or something else? Considering what you've done to stop it already, I would change to a different pad next, file the edges, and apply the Porsche anti-squeal mushroom caps (964.352.096.00 and .01). After that two caliper parts bear looking at: the spring plates (993.352.959.00 and .01) and the spring (951.352.950.00) that holds the pads in. Are they in good condition holding the pad in correctly?
I had a set of Turbo brakes on another 911 that squealed very loudly with one set of pads, and switching pads was the fix. In that case I used the Metalmasters, and they did the trick.
I had a set of Turbo brakes on another 911 that squealed very loudly with one set of pads, and switching pads was the fix. In that case I used the Metalmasters, and they did the trick.
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Bill
OEM (textar)pads.
If metalmasters are low noise, I'll give them a try.
Spring plates & springs seem OK. I checked them, as I thought they may contribute.
OEM (textar)pads.
If metalmasters are low noise, I'll give them a try.
Spring plates & springs seem OK. I checked them, as I thought they may contribute.
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That's what you get if you insist in parking your 964 on 45 degree leaf-strewn slopes! <img border="0" title="" alt="[Wink]" src="wink.gif" />
My squeaking, after the brakes were rebuilt, just stopped with time. I was told it was a 'glaze' on the discs/rotors - sounds like a OPC bluff to me - but it seems you have given the pads, and not the discs, a lot of attention. Is it safe to lightly sand your discs?
Its SO hard to be a cool dude in a Porsche with squeaky brakes!
My squeaking, after the brakes were rebuilt, just stopped with time. I was told it was a 'glaze' on the discs/rotors - sounds like a OPC bluff to me - but it seems you have given the pads, and not the discs, a lot of attention. Is it safe to lightly sand your discs?
Its SO hard to be a cool dude in a Porsche with squeaky brakes!
#5
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Mine stopped squeaking when I replaced the discs and the pads !!!
They only started squeaking after I overheated them on the track, this supports the glazing theory I suppose.
They only started squeaking after I overheated them on the track, this supports the glazing theory I suppose.
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I never had the squeaky brake problem until, at last brake job (new rotors and pads), I tried the Kevlar pads. The squealing was so bad, it was embarrassing. I replaced the Kevlars with stock Porsche pads and the squealing is gone. I wish the fix for my wife's squealing was so simple.
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Hi
The squeaking comes from the gap between the pad and the Brake piston which the anti-squeal shim is meant to compensate for, and not (usually) the surface of the pad to the disk (rotor). Its a harmonic imbalance rather than a frictional thing. You can get special sticky pads which adhere the shim to the back of the pad and are meant to stop the noise, but everything has to be really really clean for this to work.
Worth reassembling and giving them a go as. A possible side-effect of running without the shims is that you get a clunk as the pad shifts every time you brake.
Ade.
The squeaking comes from the gap between the pad and the Brake piston which the anti-squeal shim is meant to compensate for, and not (usually) the surface of the pad to the disk (rotor). Its a harmonic imbalance rather than a frictional thing. You can get special sticky pads which adhere the shim to the back of the pad and are meant to stop the noise, but everything has to be really really clean for this to work.
Worth reassembling and giving them a go as. A possible side-effect of running without the shims is that you get a clunk as the pad shifts every time you brake.
Ade.
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John
FWIW I think the problem may well be glazing due to them having been overheated at some point.This often happens on my bikes, I deglaze the pads with nothing more sophisticated than emery paper ( be careful of the dust ) and this cures it until I overheat them again!
Try a different compound when the time comes to change them.
FWIW I think the problem may well be glazing due to them having been overheated at some point.This often happens on my bikes, I deglaze the pads with nothing more sophisticated than emery paper ( be careful of the dust ) and this cures it until I overheat them again!
Try a different compound when the time comes to change them.
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I will try de-glazing the pads(man, am I sick of jacking this car up!!!!!!!!!!!)
If that fails, I'll sell it and buy a 6-speed 993, install the PSS9, supercharger & motec!!!!!
If that fails, I'll sell it and buy a 6-speed 993, install the PSS9, supercharger & motec!!!!!
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</font><blockquote><font size="1" face="Verdana,Tahoma,Arial,Helvetica,Geneva">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva"><strong>If that fails, I'll sell it and buy a 6-speed 993, install the PSS9, supercharger & motec!!!!!</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva">Hmmm, sounds like you're just looking for an excuse!
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#12
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John:
Are you dead certain that the noise is really coming from the rears?
The reason I ask is that when I had squealing problems (which seem to be re-appearing) I initially swore it was the backs. After having re-worked the backs and noticing virtually no change, I took one of those little clip on microphones with a 20 foot chord on it and then taped it to the side of the car right above the wheels, and used a tape recorder to tape the noise. Needless to say, I had to do this 4 times above each wheel. Much to my surprise, even though it really sounded from inside the car like the noise was coming from the rears, it was actually the front, and it was only one of them making all the noise.
Since then, I've devised a quicker way to determine noise. With the car cool (don't do this with hot brakes and rotors) take a high pressure hose and flush out the pad area. To do this you need to probably move the car around a little so you can get the nozzle of the hose in between the wheel spokes so it can shoot down as close as possible to being parallel to the plane of the brake rotor and try and get water in between the rotor and the pads themselves. The noise is likely not coming from this surface unless, as someone else suggested the pads are glazed, but rather the dust build up in the damping area..but if you get the water to flow in that general direction, some of it will eventually make it into the damping area as well and flush them out. I found that flushing for about a minute does the job. If you do this one wheel at a time, drive the car, and the noise disappears, it means you've found the offending wheel. When I first started doing this to isolate the problems, I found that flushing the brakes in this way could keep them quiet for about 50 miles of in town driving. If you find you have two squealers, then you'll have to do this to both wheels, but even with two squealers you should at least notice a significant change in the amount of noise.
I think I posted this tactic once before (maybe even to you) but thought I would re-post it for anyone interested.
CHEERS!!!
<img border="0" alt="[cheers]" title="" src="graemlins/beerchug.gif" />
Are you dead certain that the noise is really coming from the rears?
The reason I ask is that when I had squealing problems (which seem to be re-appearing) I initially swore it was the backs. After having re-worked the backs and noticing virtually no change, I took one of those little clip on microphones with a 20 foot chord on it and then taped it to the side of the car right above the wheels, and used a tape recorder to tape the noise. Needless to say, I had to do this 4 times above each wheel. Much to my surprise, even though it really sounded from inside the car like the noise was coming from the rears, it was actually the front, and it was only one of them making all the noise.
Since then, I've devised a quicker way to determine noise. With the car cool (don't do this with hot brakes and rotors) take a high pressure hose and flush out the pad area. To do this you need to probably move the car around a little so you can get the nozzle of the hose in between the wheel spokes so it can shoot down as close as possible to being parallel to the plane of the brake rotor and try and get water in between the rotor and the pads themselves. The noise is likely not coming from this surface unless, as someone else suggested the pads are glazed, but rather the dust build up in the damping area..but if you get the water to flow in that general direction, some of it will eventually make it into the damping area as well and flush them out. I found that flushing for about a minute does the job. If you do this one wheel at a time, drive the car, and the noise disappears, it means you've found the offending wheel. When I first started doing this to isolate the problems, I found that flushing the brakes in this way could keep them quiet for about 50 miles of in town driving. If you find you have two squealers, then you'll have to do this to both wheels, but even with two squealers you should at least notice a significant change in the amount of noise.
I think I posted this tactic once before (maybe even to you) but thought I would re-post it for anyone interested.
CHEERS!!!
<img border="0" alt="[cheers]" title="" src="graemlins/beerchug.gif" />
#13
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Bill
read your posts (I searched the archive, searchmeisters!!)
I know its the rears, as after I had done the fronts, with no improvemnt, I did therears. Noise free for nearly 20 miles!!!
read your posts (I searched the archive, searchmeisters!!)
I know its the rears, as after I had done the fronts, with no improvemnt, I did therears. Noise free for nearly 20 miles!!!
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John,
Buying a 993 wont necessarily solve the problem. Ive had a problem with sqeaky brakes for 1.5 years now. They arent extrmely bad so Im not too worried about it, the engine and the music just happens to be louder.
Buying a 993 wont necessarily solve the problem. Ive had a problem with sqeaky brakes for 1.5 years now. They arent extrmely bad so Im not too worried about it, the engine and the music just happens to be louder.
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John,
Have you checked for Carrera 2 mice? They nest where the front diff should be and make a hell of a noise when the car's sliding all over the place in winter. <img border="0" title="" alt="[Wink]" src="wink.gif" />
Roly
'90 C4 squeak free
Have you checked for Carrera 2 mice? They nest where the front diff should be and make a hell of a noise when the car's sliding all over the place in winter. <img border="0" title="" alt="[Wink]" src="wink.gif" />
Roly
'90 C4 squeak free