ACDelco brake pad #18028641 17D8

[Timothy B.]

I just purchased a set of these ACDelco 17D8 disc pads for my 67 Corvette and am wondering if I need to use the shims that came with the pads and what there purpose is.

Thanks for any information,

Tim

[Edward J.]

Re: ACDelco brake pad #18028641 17D8

Tim, the shims are to aid with pad vibrations (squealing). use them.

[Timothy B.]

Re: ACDelco brake pad #18028641 17D8

Thanks Edward,

Is there supposed to be silicone grease there also, my set did not have the little grease tube.

Thanks again, Tim

[Edward J.]

Re: ACDelco brake pad #18028641 17D8

Tim about the only thing that needs to lubed might be the metal on metal contact area where the pads slide into the calipers, and the metal pins. I use a light coating anti seize compound or a syth. grease made for high temps.

[Timothy B.]

Re: ACDelco brake pad #18028641 17D8

Thanks Ed, I appreciate your comments.

FWIW, the ACDelco 17D8 pads have a FF coefficient of friction rating marked on the back side and from my research they are a organic material.

[Duke W.]

Re: ACDelco brake pad #18028641 17D8

Most auto parts stores carry a product called "disk brake paste", which is special thick compound that you place between the pad backing plate and calliper. Some pads have it on the backing plate as delivered. It will harden over time and prevent squeaks and squeals, which is a high frequency vibration between the pad backing plate and caliper.

Most modern brake designs usually use stainless steel shims between the pad backing plate and caliper, which provide a damping effect to eliminate the noise.

Duke

[Edward J.]

Re: ACDelco brake pad #18028641 17D8

Tim, Loctite makes a disc brake quiet compound in a stick form, be careful of some of the other brake compounds that dry like cement they will take out the protective rubber boots as the pads wear, there are many types out there. You'll want a non hardening type.

[Timothy B.]

Re: ACDelco brake pad #18028641 17D8

Thanks Ed and Duke, these little shims (as they are called) look like stainless and they stick to the backing plate on the pad, should that silicone grease also be put where the caliper piston contacts the shim on the backing plate of the pad in addition to the areas where there is metal to metal.

[Duke W.]

Re: ACDelco brake pad #18028641 17D8

I don't recommend silicone grease, but it's probably a good idea to place a thin film of brake paste on all contact areas between caliper and shim/pad.

The little capsule of "grease" is for the pins on sliding caliper designs that have piston(s) on only one side, which is typical for most cars, but the vintage Corvette disk brake system is of the fixed caliper design architecture with pistons on both sides, so the caliper is "fixed" and does not "slide" over the pins as the brake pads wear.

Duke