amstel78

Some of you may remember a post of mine a while back, where I would experience a horrible creaking noise (like someone stepping on a wood floor) coming from my driver side front caliper. The noise can be heard when the car is stopped, and the brake pedal is pressed.

Anyway, Mitsu replaced the shims with another set of OE units. While that alleviated the noise, it only did so for about a month.

Today, I decided to just take the shims off that caliper completely. There's still the composite shim attached to the OEM pads which i left in place. I then applied some Permatex to the composite shim on the back of the pad and reinstalled.

Noise is gone!!!

So - while I know it's safe to run without the shims in place, my question now is this. Could there be something else wrong with the caliper to cause it to creak with the shims in? The other three calipers are fine. I looked at the shim in closer detail, and I thought perhaps the latch pins were binding on the eyelets. So I dremelled out the openings a bit more and reinstalled the shim. The creaking this time wasn't so bad, but it was still there... so the eyelets binding on the pins was an incorrect assumption.

This can only lead me to believe now that the noise starts when the piston face makes contact with the shim.

So I'm at a loss here... I suppose I will try the titanium shims next; those are not angle cut like the OEM units are. In other words, both pistons make direct contact with the shim.

Any suggestions, comments, advice?

amstel78

By the way, the pads and rotors only have about 4500 miles on them. The caliper piston dust boots look ok. I didn't feel like unbolting the caliper, so I just visually checked with a flash light, and apart from the usual brake dust buildup and dirt, the caliper looked fine.

I really am at a loss as to why a shim designed to prevent brake noise IS the source of my noise.

boomn29

iTrader: (47)

I lost one of the shims when I changed my rear brakes. So I ran w/o one for a couple weeks. I wouldn't advise it though.

Not sure if it's because I went down near metal/metal on one of my rear brakes or the fact I was missing a pad shim - but I've got some major rotor wear on the rear inside of one wheel. I'm thinking the former though; and not the shim issue. Not even sure which shim I had that was missing.

amstel78

From what you said, it shouldn't be the shim... unless, you wore through the pad backing plate as well., in which case you'd be eating through the pistons as well.

boomn29

iTrader: (47)

In my case, it's just the backside of the rear rotor that is affected.

I don't think NOT using a shim had anything to do with it, I think the damage was already done. Btw, I did reorder them from my dealer - the entire set just to get the 1 replacement. They were pretty cheap.