Anyone getting knock-back sounds from PFC 08s?
#1
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I think that is the correct term for excessive rattling of the pads in the calipers. This didn't occur with my PFC 06 setup in the front calipers. My shop is claiming that the pin in the caliper that holds the pads in place is smaller than the hole in the brake pad. This is oldd as it didn't occur from the beginning.
Do I have a caliper problem, installation issue or faulty back plate on the pad?
Note the noise is awful once the car is going 30+ mph.
thx
Do I have a caliper problem, installation issue or faulty back plate on the pad?
Note the noise is awful once the car is going 30+ mph.
thx
#2
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I haven't had an issue with the 08s up front. Did they take out the shims? Mine are still in, so I'm wondering if that makes the difference. Also, make sure you have the right pads- 7819.08.17.44
It's not likely they would have made a change to the backing plates.
It's not likely they would have made a change to the backing plates.
#3
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Are you talking about side to side or fore and aft? If fore and aft then yes, you will get that. Totally normal. Just the pad plate hitting the pin.
Last edited by LVDell; 01-07-2013 at 10:35 AM. Reason: typo
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I think that is the correct term for excessive rattling of the pads in the calipers. This didn't occur with my PFC 06 setup in the front calipers. My shop is claiming that the pin in the caliper that holds the pads in place is smaller than the hole in the brake pad. This is oldd as it didn't occur from the beginning.
Do I have a caliper problem, installation issue or faulty back plate on the pad?
Note the noise is awful once the car is going 30+ mph.
thx
Do I have a caliper problem, installation issue or faulty back plate on the pad?
Note the noise is awful once the car is going 30+ mph.
thx
When the pad gets thinner there's more space to create a bigger rattle.
Knock back is the pad vibrating up against the piston pushing it back in so when you brake you have a much longer pedal because the pad is further away form the rotor. The thinner the pad the more knock back you will see. This is why some folks tap up the pedal before braking so the pedal stays high and firm and most importantly the braking happens asap.
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This is like no other sound I've ever heard from any track car. It's not remotely driveable. Sounds like the entire front end is about to rattle and break off. This noise is way beyond a nuisance.
Let me get more details from the shop. Something must be wrong....maybe it is the wrong size pad.
Let me get more details from the shop. Something must be wrong....maybe it is the wrong size pad.
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#9
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Dell, yes, horrible, horrible noise.
Shop says the my calipers do not have the OEM clips/springs at the pin that pushes against the back of the pads. Not sure if I got that description right. In any case I still don't understand why it's doing this with my PFC 08 pads and not the 06s. More investigation needed I suspect.
Thanks to all for the comments.
Shop says the my calipers do not have the OEM clips/springs at the pin that pushes against the back of the pads. Not sure if I got that description right. In any case I still don't understand why it's doing this with my PFC 08 pads and not the 06s. More investigation needed I suspect.
Thanks to all for the comments.
#12
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I have the 08's, no "quiet" springs, and the pads do rattle around when they start to wear. What rotors do you have? Are they floaters? If yes, that might be an additional source for the clackity-clack.
#14
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Interesting. I wonder if you could install those in the front, or if it's a "typo"? Fronts have nuts on the through-bolts, it's the rears that have the spring pins.
I have the 08's, no "quiet" springs, and the pads do rattle around when they start to wear. What rotors do you have? Are they floaters? If yes, that might be an additional source for the clackity-clack.
I have the 08's, no "quiet" springs, and the pads do rattle around when they start to wear. What rotors do you have? Are they floaters? If yes, that might be an additional source for the clackity-clack.