72 Brake Pads Rattle

[Al S.]

Since I've performed a complete brake job on my 72 it seems to have rattles comming from all four corners. I know it's the pads because it I didn't notice this before the brake job, and when I step on the brakes over bumps it's quiet. Anti-rattle clips aren't available for these are they? I hope to have the car judged some day and want to do it right. Any input is welcomed. (It sounds like the 72 GMC tow truck I use to drive back in high school!)

[Joe L.]

Re: 72 Brake Pads Rattle

Al-----

I'm not sure what you mean by "rattling". However, I assume that you're not talking about brake squeal which is usually much more pronunced when actually braking rather than at other times.

In any event, brake pad noise can otherwise be generated in 65-82 Corvette brake systems from 2 sources: contact of the pad backing plate with the pad retaining pin AND contact of the pad backing plate ends with the caliper. The former condition is usually noticed as a single "click" when reversing direction of the car. This is caused by rotation of the pads and the resulting contact of the pad pin with the front or rear of the oblong pad pin hole in the backing plate.

The second condition is caused by contact of the pad backing plates ends with the calipers, themselves. Usually, this is only a problem when rotors have excessive runout, causing the pads to move very slightly inward and outward. There are 2 types of aftermarket devices which can be used to quiet this condition. One involves the use of horseshoe shaped plastic shims which "insulate" the pads from the calipers. The other involves the use of "sleeves" made of a tough polymer material which fit over the ends of the brake pad backing plates and also "insulate" the pad backing plates from the calipers. These are the better of the 2 "solutions". However, both "solutions" are really only a "band-aid" approach to the problem. The real solution is correcting the run-out condition which WILL cause other problems. However, if the run-out is within spec (absolutely no more than .005") and pad backing plate noise is still a problem, the "sleeves" I mentioned can be installed on the backing plate ends.

1965-82 Corvette brake systems never used any anti-rattle clips in their original installation. That's because 1965-82 Corvettes use a constant-contact type of brake piston system in which the pads are held in constant contact with the rotor by the action of springs behind each piston. Most other braking systems, which use single or dual piston FLOATING calipers, do not use the constant contact system; it is pretty much only used in fixed caliper systems and the 65-82 Corvette system is one of the last fixed caliper systems in use. Since the 65-82 Corvette system is constant-contact, no anti-rattle devices are used or should be required.

[Al S.]

Re: 72 Brake Pads Rattle

Joe,
Thanks for your help. (It isn't a squeal it's a rattle.)