Ok, this is rediculous.

Here is my original post on this issue that has been six months..

https://www.rx7club.com/3rd-generation-specific-1993-2002-16/mysterious-brake-clunk-need-council-503536/

This brake clank has been frustrating and I could in no way figure out what was going on......and I searched a bunch of times for answers here.

Over the weekend I dug out the shims that were on the front pads from the old set that I kicked under my work bench. These shims are a slim metal sheet in the shape of the pad. I put them back on the car (4 in all) and just like that....no brake clank. Zero. Nada. Complete silence.

I don't have a clue why this works and the difference is clear. Bad squeaking, creaking, and clanking at low speed vs. nothing at all. Maybe somebody could explain this to me. I can't see why this would have such a dramatic effect.

The only difference I can tell is the shim is just a smidge longer than the pad.???

I figured I would post this because there are a bunch of others here that still have problems with this too.

 

The shims provide just enough springiness to the pad/caliper assembly to damp out any vibrations and chatter as the pad moves. Yes, they can make a big difference.

Dave

 

I have the same exact symptoms with the Hawk HP pads that are on the car. A clunk at low speeds and horrible squeeking, also at low speeds. Unfortunately, I don't have the old pads or shims. Any way to fix the shims that are on there?

 

go figure, i have the same issue. no clue what pads are on there right now, but that clunk and semi-tailer sounding screech are killing me. everytime i slow down adn low speeds i look around looking for a semi... Without the old shims, how can i modify the existing ones?

 

I bought a brand new set of shims. Still have the clank. Glad to hear that yours is fixed though! Maybe they're installed wrong, but I've re done them a buncha times and there aren't that many ways that those things fit on, so I still don't know whats causing the clank. If only it were that easy in my case.

 

Terrible brake squeal at low speeds is due to the pad(s) vibrating back and forth across the caliper piston face. The shims act as a buffer between the pad and piston and damp the vibration so you get no squeal. Some pads have shims built in but mine have always been quieter with the stock shims in place regardless of pad type.

The blue semi-adhesive goo you put on the back of brake pads has the same effect but typically doesn't last as long.

 

What I noticed on mine is that the Hawk pads are smacking into the caliper. I've had my brother press on the brake while I rotate the tire for confirmation. You can see the pad move up and hit it. I do have the shims so I dont know what would cause this. Cant be the rotors since they're new and I did check them for uneveness with a dial indicator. Any help would be appreciated.

 

I have a fair amount of adhesive between the shim and the pad. I am sure that has something to do with it... Like I said, this is a real mystery....

 

I had that on an old set or rear pads as well. The backing plates were a tad small and you'd hear the pads tap the caliper each time you hit the brakes.

 

Is there anything to cure the problem. My pads are new

 

If you have HP+, then that is normal--they're race pads. I uninstalled mine....they had great initial bite, but the squeeeeeeling was driving me insane.