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hiosilver
02-14-2006, 09:13 AM
I just installed a new set of Raybestos ceramic brake pads on all four wheels. I followed the instructions to the letter when it came to lubing the areas where the pads and caliper have to move. Since our brakes only have one pin that actually holds the caliper to the carrier, it has a little bit of play. At slow speeds tapping the brake pedal produces a clunk when the caliper moves. Does anyone else's do this? Is there anything I can do to make it better? The old worn out pads never made the noise but those were all gummed up and very dirty.

Thanks

Pat

ProfChaos
02-15-2006, 07:10 AM
I experienced a similar situation with the rear brake on my motorcycle (a Honda VTR1000F SuperHawk): The pin anchoring the top portion of the rear brake pads had developed a groove and was also irregular with heavy corrosion; the pads were thus not free-floating: the top-outer pad would occasionally get hung-up in the groove. We replaced the corroded and worn caliper pin, and things straightened right out.

Though I'm not sure of the physics behind the Cobra's "floating calipers," based upon this experience with motorcycle brakes, I would be sure to check that a caliper pin is not either worn or corroded, and thus hanging-up a brake pad's movement in some way.

Another issue might be severely warped brake rotors (the front, more likely). A few months ago, I heard a weird "clunk" (and a high-pitched brake-wear-indicator sound) at the same time that I discovered that my front brake rotors were horked. I discovered this because the severely warped rotors led to radically uneven brake pad wear and came also with associated wierdnesses, including an annoying steering wheel oscillation (like I was forever driving on a Florida road crown).

If your rotors are indeed warped, it should be fairly easy to tell, and you might even be able to see discoloration of the rotors from when they got cooked.

best wishes on your finding a solution,
--Professor Chaos

flynfink
02-15-2006, 01:58 PM
I just installed a new set of Raybestos ceramic brake pads on all four wheels. I followed the instructions to the letter when it came to lubing the areas where the pads and caliper have to move. Since our brakes only have one pin that actually holds the caliper to the carrier, it has a little bit of play. At slow speeds tapping the brake pedal produces a clunk when the caliper moves. Does anyone else's do this? Is there anything I can do to make it better? The old worn out pads never made the noise but those were all gummed up and very dirty.

Thanks

Pat

Normal.. Listen when you backup and tap the brakes..

Did you move the noise isolator clips from the old to the new or use the new ones? I find the aftermarket one not as good as the OEM's, so I just keep using the one that came on the car when I put new pads on.

dewone
02-15-2006, 02:41 PM
If you no longer have the clips go to the auto parts store and get some brake silicone and apply it to the back of the pads. I get the some thing on my F-150 every time I forget the silicone.

flynfink
02-15-2006, 03:07 PM
:thumbsup:

Permatex calls it disk brake quiet.

Just don't use it on a car that see's track duty..

hiosilver
02-15-2006, 07:44 PM
Thanks for all the replies. I did use the new clips that came with the pads and I used the silicon lube that also came with the pads. I have some of the blue sticky stuff that I used on other cars so I will try that this weekend. It only happens when you are going very slow and tap the brakes solidly then get off of them. Unfortunetely, I threw away the old clips. I measured the rotors when I changed the pads and they were well within tolerence and had almost no runout.

I will let everyone know what actually works to quiet them down.

Pat

QuickSilver
02-16-2006, 09:05 AM
I too have a clunk on my brakes right after I had my rotors turned. The guy said that it is normal but I know better. I think something happened when fisher tires took off my brakes. fisher tires was in a hurry when they did it. It kinda sounds like the pad are not touching the rotor and when I apply pressure to the brakes they clunk down on the rotors.:(

jason :rotf:

flynfink
02-16-2006, 10:37 AM
OK guys, one more time.. this is not unusual nor is it a problem. I have two Cobra's and it's normal with the stock PBR calipers (floating) to have some clunking or other noise, when making a slow speed application of the brakes, especially when backing up. The pads will shift a bit depending on how tight the anit-rattle clips keep the pad to the caliper.. The are times when I haven't used the anti-rattle clips and the noise is more pronounced..

QuickSilver
02-17-2006, 11:29 AM
I understand but I have had my cobra for 2 years and never hade this happen untill i got the front rotors turned. It also has a metal squeaking sound when no pressure is added to the braks while in driving speeds but the brake pads are a few months new. :(
Jason :starwars:


2001 Silver SVT Mustang Cobra:bounce: <?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" /><o:p></o:p>

18 Chrome Steeda ultra lights rims:D

Sumitomo 265/35/ZR18

Steeda racing lug nuts

Steeda billet bullet door locks

Steeda 4 bolt adjustable caster chamber plates

Steeda shifter bezel w/name

Maximum motorsports k member bar

3:55 rear gears

MGW 3-D chrome/billet cobra shift knob

UPR Blu Thunder NS shifter

Baer Eradispeed vented crossed-drilled and slotted rotors:thumbsup:

Bassani off-road X pipe w/no cats:007:

Steeda Cat-Back Exhaust made by Borla:eek:

K&N air filter charger

Diablo sport chip

UPR rear bumper inserts

20% black window tint

Chrome Cobra license plate

SVT Cobra Mustang Club Third Brake Light Decal

SVT Cobra Mustang Club Dash Board Badge

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flynfink
02-17-2006, 01:21 PM
Give one of the Knoxville guys a ring and have them help you with it..

Too many small things to look at, especially since I now see you have aftermarket rotors.. Pins, stuck pistons....

BTW, my slotted rotors, like the cross drilled brembo rotors on my motorcycles, make a really neat sound when the pads hit them..

cobrabitn
02-17-2006, 10:16 PM
Jason,

What Jeff is saying is right, my 94 Coupe does it especially when you are backing up. The Pace car doesn't do it but that's because nothing has ever been taken off the car concerning rotors or brakes. It probably has something to do with the clips but the calipers do float and I'm sure it has something to do with that. I don't think it is really anything to worry about as long as when you hit the brakes, you stop. :) My coupe has done it for years now, especially since it has seen track duty! :thumbsup: If you are not sure or want someone in the Knoxville area to look at them, I would ask Rick as I am sure he has changed pads time and time again. :D

Tony

hiosilver
02-19-2006, 10:38 PM
OK, here is what I found--at least for the Raybestos pads. The brake quiet sticky stuff won't work with these pads as they are solidly attached to either the outside of the caliper or the inside of the pistons. The stock pads have a different anti-rattle spring or clip on them that do not transfer to the new pads. The new pads however, have a spring clip on them that double as a wear indicator and must be sprung out just a bit to make sure there is enough spring tension on them to keep the pads tight in the caliper. I eliminated about 90% of the clunk at slow speeds by bending the spring clips out so they provided more tension. The 10% that remains is a non-issue as it is very minor. Before I did the fix, mine were so loose that I could hear the pads rattling around when I hit a bump.

I guess the bottom line is that it depends on the manufacturer of the pads and what they use as an anti-rattle spring as to how much clunk you get. I appreciate all the expertise and experience you guys have--it sure helped me get my brakes quiet. Can't wait for summer so I can take the top down for the first time.



Pat

dewone
02-20-2006, 08:55 AM
Gald to see you got that taken care of.

QuickSilver
02-20-2006, 09:16 AM
Thank you Jeff and Tony. I will have the brakes looked at real soon. can't stand the metal squeaking noise nor the rattle. Thanks again.
Jason :starwars:


2001 Silver SVT Mustang Cobra :rotf: :rotf:

18 Chrome Steeda ultra lights rims

Sumitomo 265/35/ZR18

Steeda racing lug nuts

Steeda billet bullet door locks

Steeda 4 bolt adjustable caster chamber plates

Steeda shifter bezel w/name

Maximum motorsports k member bar

3:55 rear gears

MGW 3-D chrome/billet cobra shift knob

UPR Blu Thunder NS shifter

Baer Eradispeed vented crossed-drilled and slotted rotors

Bassani off-road X pipe w/no cats

Steeda Cat-Back Exhaust made by Borla

K&N air filter charger

Diablo sport chip

UPR rear bumper inserts

20% black window tint

Chrome Cobra license plate

SVT Cobra Mustang Club Third Brake Light Decal

SVT Cobra Mustang Club Dash Board Badge

SVT Cobra Mustang Club Engine Badge