C2 Caliper rattle

[Brian K.]

Hitting bumps especially on the front the pads rattle quite a bit. I have rebuilt all calipers and new springs (non o ring type). I even replaced the worst offender with a reconditioned one from Muskegon Brake. Still no better.

It still rattles like crazy and all mounts are tight. Any one else have this issue?

[Patrick H.]

Re: C2 Caliper rattle

It's the pads rattling, not the calipers. The 70-72 PV manual even indicates that this is supposed to happen, and you might fail if it doesn't.

Your rattling sounds worse than the average, but you might try different pads if it REALLY bothers you. Or, try the anti-squeak brake pad spray on the metal side of the pads. That got rid of the rattle on a car I had. Of course, I had to then remove it for a PV...

[Brian K.]

Re: C2 Caliper rattle

Thanks Patrick. Yes I know it's the pads. Never figured that would be a pv item but not judging the car. Are you referring to the stuff that's goopy and sort of bonds it to the pistons?

[Patrick H.]

Re: C2 Caliper rattle

Yep, the goopy stuff. I suspect that if your pads were a bit longer (?) the noise would decrease. But, the spray stopped it for us.

From the 70-72 PV Manual:
"A click may be noticed at low speed on initial application and is considered normal. A similar noise while traversing a bump without the brakes applied is also normal. The absence of these clicking sounds may indicate application of a squeal-reducing adhesive to the back of the pads. Such an adhesive is not proper and cause for failure."

[John S.]

Re: C2 Caliper rattle

Yep, the goopy stuff. I suspect that if your pads were a bit longer (?) the noise would decrease. But, the spray stopped it for us.

From the 70-72 PV Manual:
"A click may be noticed at low speed on initial application and is considered normal. A similar noise while traversing a bump without the brakes applied is also normal. The absence of these clicking sounds may indicate application of a squeal-reducing adhesive to the back of the pads. Such an adhesive is not proper and cause for failure."

why are you recommending any type of "goopy stuff" or adhesive when the engineers stated it caused failures? have you any idea why anything that is slightly adhesive causes brake failure?

[Patrick H.]

Re: C2 Caliper rattle

why are you recommending any type of "goopy stuff" or adhesive when the engineers stated it caused failures? have you any idea why anything that is slightly adhesive causes brake failure?

Where did you get the idea that some engineers state it cause failures?

The quote above is from the PV manual. If the brakes DO NOT click, then you fail your Performance Verification test.
That's all.
Well, it's a lot, but...

The brakes work just fine.

[John S.]

Re: C2 Caliper rattle

sorry, I misread the part about the failure meaning loss of judging points. in the late 70s I did contact engineers at Chevrolet because of piston leakage with new brake shoes and calipers. at that time a blue colored anti-squeak compound was included with the new shoes. reply from Chevrolet was the four piston calipers are suppose to be "free floating". The use of any sticky substance causes the piston to adhere to the back of the brake pad and when braking the small sideway movement in the brake pad and the attached piston allows the seals to open up and leak. Air enters the system at the same time. Many times squeaking occurs when the side of the brake pad's backing plate makes contact with the inner caliper surface while braking. the best solution for this is a shim that prevents contact of the two metal surfaces.

[Timothy B.]

Re: C2 Caliper rattle

Also, many times the squeak is caused from run out in the rotor moving the pads as the wheel moves,0 I had that problem on my car.

[Jim T.]

Re: C2 Caliper rattle

Also, many times the squeak is caused from run out in the rotor moving the pads as the wheel moves,0 I had that problem on my car.

I agree about noise because of moving pads. In 1974 I took my one owner 1970 to the largest Chevrolet dealer in Dallas about noise from the rear. The dealership mechanics drilled out the rivets retaining the trued brake discs to the spindles of both wheels and installed new wheel bearings and spindles. The new noise I heard after this warranty work was to much rotor run out because moving the pads. Only heard it at low speeds and with the windows down in my air conditioned Corvette. Later air in the calipers developed and enough caused loss of brakes to the rear calipers. Years later after many episodes of bleeding air from the calipers I removed my rear spindles and discs and sent them to BAIRS to have the disc rotors riveted to the spindles and trued. This was done about 30 years ago and have had no air in the calipers to bleed since this was done. Drove it today, great brakes.
My original owner 1968 still has its factory installed rear spindles and brake discs riveted and have never had air in the calipers and no noise from the pads.

[John S.]

Re: C2 Caliper rattle

Brian, if you don't come up with a solution, I have a set of shims for the front calipers that should solve your problem. all you have to do is insert them on the sides of the caliper. no disassembly necessary and the shims pull right out if you need to replace them. I think i only replaced or lost one in 35 years on the C3 I owned and shims were on all four wheels. If interested send me a email with your address and I will you mail you a set of shims. Price for shims and shipping will be $26 only payable if the shims do reduce or stop the "rattle".

[Brian K.]

Re: C2 Caliper rattle

Thanks John,

Bair's did my rear rotors/spindles and I did do the runout on my front rotors so i know i'm good there. Many of my friend's C2's don't have this complaint. I know it's slop in the caliper/pad interface and it seems a spring or something to take up that slack is the solution. I don't have a problem using a little goop but it seems that may wear away and bind the piston to the pad?

Are these shims something you made? I would be interested in them.

Thanks!

[Michael W.]

Re: C2 Caliper rattle

I used something similar to this product, worked well

http://www.mamotorworks.com/Corvette/product/brake-anti-squeak-kit-602720-1

[John S.]

Re: C2 Caliper rattle

I used something similar to this product, worked well

http://www.mamotorworks.com/Corvette...k-kit-602720-1

Mike, what prevents the insert from falling off? this product does do the same thing that the shims I have, but mine were a horseshoe design.

[Michael W.]

Re: C2 Caliper rattle

The shims are a split tube that slide vertically into place. They seem to grip tightly enough to hold themselves in place.

http://image.mamotorworksmedia.com/production/website/articlefiles/installfiles/602720_Installation_Instructions.pdf

[John S.]

Re: C2 Caliper rattle

The shims are a split tube that slide vertically into place. They seem to grip tightly enough to hold themselves in place.

http://image.mamotorworksmedia.com/p...structions.pdf

brian, since these inserts seem to stay in place, I would think they would solve your problem.