'66 brake squeal

[Rob A.]

I installed "stick on" anti squeal shims to the brake pads to try to stop the squeal, but it didn't help. I believe the pads are semi-metallic, but my understanding is that the squeal is not related to the pad material, but the vibration from the pistons against the back of the pads....should I try anti-squeal compound?

[Joe L.]

Re: '66 brake squeal

Rob-----

Many folks SAY that brake squeal is always caused by piston-to-pad backing plate vibration. However, I don't buy it. That condition is definitely ONE of the things that cause brake squeal, though. Pad compound is ANOTHER of the things that cause brake squeal. Friction surface GLAZING is another thing that causes squeal. You can try the anti-squeal compound; it's easy enough to apply on a Corvette. I don't think it will solve the problem, though.

[John H.]

Re: '66 brake squeal

Rob -

Chances are the problem will disappear if you change to OEM-type organic pads, which will also reduce required pedal pressure; when these cars were built, they had organic pads, not semi-metallic.

[Gary Schisler]

Re: '66 brake squeal

I have had good luck cutting the leading and trailing edge of the brake pads at about a 45 degree angle. I was told, rightly or wrongly, that the majority of brake pad squeal is related to the extremem angle that the face of the pad is to the rotor. This has worked for me on my 72 and also on my 79 Mercedes which has a braking system that is almost identical to the Corvette.

Gary

[Jim T.]

Re: '66 brake squeal

Gary I think there was an article in the Corvette Restorer about cutting the pads, anyway I read about it somewhere.

[John H.]

Re: '66 brake squeal

Jim -

We did that (chamfer the edges of the pads) as the production fix for the same issue on the Viper starting in '96, and it works fine until the pad wears down to the point where the chamfer started.

[Joe L.]

Re: '66 brake squeal

John------

Pads on some modern-era cars have a very deep bevel on the leading edge of the friction surface. So, the bevel remains until the pad is, essentially, worn down to the friction surface minimum thickness. The problem, though, at least as I see it, is that there is a fairly large amount of friction surface that is lost to the braking effort in the process. Of course, this may be taken into account in the brake design. Still, it "doesn't feel right to me".

[Rich G.]

Re: '66 brake squeal

Jim

Yes, there was an article in the Restorer about this. Maybe more than a year, but less than 2 years ago. It reprinted a service letter from 1966 that showed how to bevel the edges. I never did it. My 66 squeals less than it used to. Must be wearing out the pads!

Rich #38594

[Rob A.]

Re: '66 brake squeal

John,

My local Autozone has what they call "organic, semi-metallic". I assume true OEM type pads have no metal in them...? If so, do you know what chain type auto store might carry them?

[Joe L.]

Re: '66 brake squeal

Rob-----

Order a set of Delco #17D8, aka GM #18028641, and you'll have what you seek. These are quite inexpensive---about 30 bucks per axle set from Delco dealers.

[Kevin M.]

Re: '66 brake squeal

67 the same I assume?

Kevin

[Joe L.]

Re: '66 brake squeal

Kevin-----

Yes, it's the same part number for 1965-82 Corvettes except those equipped with J-56 and, of course, those 316 1965's equipped with drum brakes.

These pads will work, though, for the rear pads of J-56-equipped cars.

[Rob A.]

Re: '66 brake squeal

Joe,

I installed a set of the pads(Delco #17D8)in the rear and the squeal stopped, hopefully for good. I'll install the front pads at a later date.

Thanks...