Rattle Front Disk Brakes
#5
Drifting
Member Since: Sep 2003
Location: 1994 LT1 Coupe 6-speed with FX3 & 2000 LS1 Vert 6-Speed with F45 Hunterdon County, NJ
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Not sure if your 93 has the same brake pad/caliper configuration as our 94, but in case it does, here's a few things to look at:
1. If you removed the caliper mounting bracket, what torque on the mounting bolts did you use? The 94 manual (and I remember many other years too) had an error for the torque, should be a max of 137 ft lb -- more will likely break the bolts. So, any chance the bolts have broken? BTW, FSM recommends replacing these bolts whenever removed and the new ones come with "adhesive".
2. the inner and outer pads have a backing plate with two metal-cup-like 'spring' retainers which slip into the pistons on one side, and the caliper bracket's two holes on the other side -- any chance your replacement pads were not OEM (PBR - Australia) and were missing these backing plates?
3. The caliper is held into the caliper-mounting bracket by the pad's tabs trapped under a 'retainer pin' with its 'circlip' holding the 'pin' in place. The PBR pad kit comes with two different length 'retainer pins' with "circlip grooves cut in different positions" (one for 'base' and the other for 'heavy duty' (J55?)). Might the wrong pin lengths have been installed or the 'circlip' left off or broken off (especially if reused)?
4. Might the brake system be J55 (heavy duty) and the 'base' brake pads installed instead (or vica-versa)? Or might the brake system have been upgraded and the wrong pads were installed (C5 brakes)?
1. If you removed the caliper mounting bracket, what torque on the mounting bolts did you use? The 94 manual (and I remember many other years too) had an error for the torque, should be a max of 137 ft lb -- more will likely break the bolts. So, any chance the bolts have broken? BTW, FSM recommends replacing these bolts whenever removed and the new ones come with "adhesive".
2. the inner and outer pads have a backing plate with two metal-cup-like 'spring' retainers which slip into the pistons on one side, and the caliper bracket's two holes on the other side -- any chance your replacement pads were not OEM (PBR - Australia) and were missing these backing plates?
3. The caliper is held into the caliper-mounting bracket by the pad's tabs trapped under a 'retainer pin' with its 'circlip' holding the 'pin' in place. The PBR pad kit comes with two different length 'retainer pins' with "circlip grooves cut in different positions" (one for 'base' and the other for 'heavy duty' (J55?)). Might the wrong pin lengths have been installed or the 'circlip' left off or broken off (especially if reused)?
4. Might the brake system be J55 (heavy duty) and the 'base' brake pads installed instead (or vica-versa)? Or might the brake system have been upgraded and the wrong pads were installed (C5 brakes)?
#6
Thanks for the thoughts but;
The caliper mounting bracket bolts are good and tight.
The pads are not OEM but they had the cup like springs and fit in perfectly.
The retainer pin fits properly and the circlip is in place.
When I examine the caliper in place there is the slightest bit of play. It would seem that this is what causes the rattle when I hit a bump. I'm thinking that there should be some type of spring that would hold the caliper in place and absorb the shock.
The caliper mounting bracket bolts are good and tight.
The pads are not OEM but they had the cup like springs and fit in perfectly.
The retainer pin fits properly and the circlip is in place.
When I examine the caliper in place there is the slightest bit of play. It would seem that this is what causes the rattle when I hit a bump. I'm thinking that there should be some type of spring that would hold the caliper in place and absorb the shock.
#7
Le Mans Master
If you don't have anti rattle clips in place every time you hit the brake pedel its going to make noise and every time you hit a bump its going to rattle, plan and simple...WW
#8
Le Mans Master
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Let's clarify. You said that you didn't remember any springs and then say that they are there. Did you check? The springs/clips people are talking about are at the far right in the 2nd picture and, when attached to the pads, fit into the bracket as shown in the 1st. Both pads on each caliper need them. You'll be able to manually move the caliper up & down, but should feel the resistance of the springs.
#9
That looks like what is missing. I have never seen them before, the anti rattle clips. I guess I can pick them up at an auto parts store.
Thanks, that should cure the problem.
Thanks, that should cure the problem.
#11
Le Mans Master
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Edit - Now I understand what you meant by "cup like springs"; the two which hold the pad into the caliper.
Last edited by jrp; 07-30-2009 at 01:22 PM.
#12
Le Mans Master
got mine at Advance Auto Parts, just a couple of bucks. What gets me is the previous owner went to a Chevy dealer to get the brakes done and THEY even left them out
#13
Instructor
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The Hawk website doesn't distinguish between J55 and regular... aren't the pads the same? I just bought a set of Hawk HPS pads, planning to install them next week... first time for me... do I have the right pads?
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Ronald Howard (11-22-2020)
#15
Great photos. Thanks I am definetly missing those anti rattle clips. They weren't on the old pads and did not come with the new ones. Having trouble getting them from a store around here. One place wanted over $36 for the clips. Next week I'll be in an area where there is an Advance Auto Parts as you suggested above. Thanks again. I'll finally be rattle free.
#16
Melting Slicks
Same pads and I also have some anti-rattle clips lying around as well so now you have 2 people that can get them to you, $36 is a joke for those. I don't think it hurts anything to drive around without them, it just rattles.
#17
Melting Slicks
NAPA also has them:
http://www.napaonline.com/MasterPage...re+Kit+-+Front
(UP 83014A if the link doesn't work) That's where I got mine when I determined that was the cause of my rattling last year.
http://www.napaonline.com/MasterPage...re+Kit+-+Front
(UP 83014A if the link doesn't work) That's where I got mine when I determined that was the cause of my rattling last year.
#18
Drifting
Member Since: Sep 2003
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FYI, now noticed the aforementioned anti-rattle devices -- must have been late and didn't remember installing them, so perhaps they came already mounted to the new GM PBR pads I installed.
The FSM calls them a 'Bias Spring' and shows it mounted to the left side of the outer pad (e.g. passenger side would be upper edge or trailing edge of pad).
And sorry, but I can't also offer old clips as I threw out all the old parts years ago...
The FSM calls them a 'Bias Spring' and shows it mounted to the left side of the outer pad (e.g. passenger side would be upper edge or trailing edge of pad).
And sorry, but I can't also offer old clips as I threw out all the old parts years ago...
#19
Le Mans Master
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St. Jude Donor '10-'11-'12-'13
Let's clarify. You said that you didn't remember any springs and then say that they are there. Did you check? The springs/clips people are talking about are at the far right in the 2nd picture and, when attached to the pads, fit into the bracket as shown in the 1st. Both pads on each caliper need them. You'll be able to manually move the caliper up & down, but should feel the resistance of the springs.