Original brake pad clips/backings - keep or toss?

[z0ned]

Hey all. Having worn the original Subaru front pads down to nothing in about 27k miles, I just changed out the front brake pads on my 06 limited for new EBC ones. Did it myself, procedure was easy enough and went totally fine. (Damn those caliper pistons are a pain in the ass to press down though, my hands are still sore!) Bed-in is coming along well, everything looks good.

Just one question: The original pads had various ancillary metal hardware attached to them: slotted metal backing shims, some other metal brackets with tabs that wrapped around the sides at certain places, and a small L-shaped clip/bracket (not sure what to call it) that fit at the bottom corner hole where the pin goes through. I presume that these parts served some purpose of noise reduction, or of increasing the life of the original pads. Should I reuse any of these original metal clips/brackets with the newly installed pads, or is it best to discard them all? The new pads came only with adhesive hard plastic backing shims, which of course I installed. Will reusing the original metal clips help reduce noise and extend the life of the new pads too, or just get in the way and cause problems?

Thanks!

[EvoEatr]

Whenever available personally I make sure I get new hardware for the brake job such as all the metal clips/metal shims for the back of the pads and such, however If I cant get them for some reason I always reuse the old stuff..clean it up with a wire brush and lubricate it a little with some caliper grease..The little "L" shaped metal "clip" I believe your talking about sounds like the wear indicator (placed at the bottom of the inboard pad)..If you can and if the new pads dont have one I would def. attempt to reinstall that...The manufacturer wouldnt have put those little metal clips there if they didnt serve a purpose... ...Since this is an 06' I'm assuming you have the front red SUBARU 4 pot calipers....FWIW I almost ALWAYS at least turn the rotors if not replace them when I replace a set of brake pads...

[z0ned]

Ok, got a hold of a service manual, here's as much detail as I can share about what I see, expressed as best I can. Hey, maybe this will help someone someday.

Each front brake pad has corresponding to it three metal ancillary parts, the brackets/clips I referred to. These three parts are diagrammed and labeled in the service manual as:

- Inner shim
- Outer shim
- Spacer

"Inner shim" is a thin metal backing plate that is the same shape as the pad and goes directly on the back of the pad. Several rounded slots are cut out of the middle of its face. A few small tabs extend from it and right angle around the long sides of the pad, I presume to hug the pad and keep it in place. The service manual instructs to put caliper grease between this Inner shim and the back of the pad when installing.

"Outer shim" is a completely flat, thin metal unslotted plate that goes outside of Inner shim. It is the same thichness and thin metal material as Inner shim, but doesn't have any tabs or slots - it's just a flat piece of metal. This Outer shim ultimately intervenes the caliper pistons and the Inner shim. Outer shim is as long as Inner shim but somewhat less wide as it ends diagonally towards the top. I think its purpose is, together with Inner shim, to act as a spacer, and particularly also to give the caliper pistons something completely flat to press directly on.

"Spacer" is the L-shaped bracket/clip I mentioned. It is not the squeal bar. (The squeal bar on the original pads, as I actually found, is permanently riveted to the inside passenger-side pad, go figure.) This Spacer is small, corner-shaped, and has various appended tabs that allow it to fit about the lower back corner of the pad, Inner shim, and Outer shim combined. And it has a hole that matches with the hole the big lower Pin goes through. Given its name, its purpose is surely to space the pad from the surfaces of the caliper body against which gravity would have it rest.

My quandry is that the new third-party pads I installed came with their own hard plastic adhesive backing. Since I applied this backing and since it already seemed to have the correct width and placement to serve the purpose of the "Inner shim" and "Outer shim", I went ahead of left them out during installation. I did, however, use the "Spacer" L-shaped clip, because it seemed important, and because nothing that came with the new pads would have substituted for it.

Now I just wonder whether the Inner shim and Outer shim do something the hard plastic adhesive backing doesn't, like noise control wise. I can put them back on, it'll just be more work. I'm inclined to wait and see how noise behaves after several 100 miles... it's only been ~40 miles on the new pads so far and they are creaking when rolling to a stop under light brake pedal pressure - but that's normal and expected this early. So wait and see is my choice. What do you all say?

[EvoEatr]

Ok, got a hold of a service manual, here's as much detail as I can share about what I see, expressed as best I can. Hey, maybe this will help someone someday.

Each front brake pad has corresponding to it three metal ancillary parts, the brackets/clips I referred to. These three parts are diagrammed and labeled in the service manual as:

- Inner shim
- Outer shim
- Spacer

"Inner shim" is a thin metal backing plate that is the same shape as the pad and goes directly on the back of the pad. Several rounded slots are cut out of the middle of its face. A few small tabs extend from it and right angle around the long sides of the pad, I presume to hug the pad and keep it in place. The service manual instructs to put caliper grease between this Inner shim and the back of the pad when installing.

"Outer shim" is a completely flat, thin metal unslotted plate that goes outside of Inner shim. It is the same thichness and thin metal material as Inner shim, but doesn't have any tabs or slots - it's just a flat piece of metal. This Outer shim ultimately intervenes the caliper pistons and the Inner shim. Outer shim is as long as Inner shim but somewhat less wide as it ends diagonally towards the top. I think its purpose is, together with Inner shim, to act as a spacer, and particularly also to give the caliper pistons something completely flat to press directly on.

"Spacer" is the L-shaped bracket/clip I mentioned. It is not the squeal bar. (The squeal bar on the original pads, as I actually found, is permanently riveted to the inside passenger-side pad, go figure.) This Spacer is small, corner-shaped, and has various appended tabs that allow it to fit about the lower back corner of the pad, Inner shim, and Outer shim combined. And it has a hole that matches with the hole the big lower Pin goes through. Given its name, its purpose is surely to space the pad from the surfaces of the caliper body against which gravity would have it rest.

My quandry is that the new third-party pads I installed came with their own hard plastic adhesive backing. Since I applied this backing and since it already seemed to have the correct width and placement to serve the purpose of the "Inner shim" and "Outer shim", I went ahead of left them out during installation. I did, however, use the "Spacer" L-shaped clip, because it seemed important, and because nothing that came with the new pads would have substituted for it.

Now I just wonder whether the Inner shim and Outer shim do something the hard plastic adhesive backing doesn't, like noise control wise. I can put them back on, it'll just be more work. I'm inclined to wait and see how noise behaves after several 100 miles... it's only been ~40 miles on the new pads so far and they are creaking when rolling to a stop under light brake pedal pressure - but that's normal and expected this early. So wait and see is my choice. What do you all say?

Sometimes the creaking noise is normal even when the pads are fully worn in (burnish procedure)...I have this noise from the front of my Legacy...its just the extremely small amount of space between the pad and the caliper and the pad and the rotor...it kind of sounds like a door creaking..lol...

[devilfluff]

Do not re-use the old shims. Unless the new pads came with information stating otherwise, they come with any shims required.

[z0ned]

Well I got various conflicting answers from forums / the hspn video tutorial / the subaru service manual / the 3rd party pad manufacturer's website / friends / coworkers, etc. Not having any consistent answer, but continuing to endure the loud creaking noise I knew couldnt be right, I decided to just do the work. And now.. as I found out.. the correct answer:

Yes, you have to reuse the original metal Inner Shim and Outer Shim (and Spacer bracket) pieces with new brake pads. They are a part of the assembly and while the brakes may technically work "the same" without them, you want them.. because without them you'll have a nasty creaking noise.

The plastic adhesive backing that may be included in the box with the new pads is just a supplemental noise reduction shim. Use it of course, but understand it does not stand in place of the original shim parts. The original shim parts can fit right on over the supplemental one. Then the whole assembly is plenty thick, but it'll fit in fine as long as you press the caliper pistons all the way down.

I know this because I disassembled things back down to the pads today, reintroduced the Inner shim and Outer shim that I had previously left out (as I described in my posts above), and now the creaking noise is gone.

[EvoEatr]

Whenever available personally I make sure I get new hardware for the brake job such as all the metal clips/metal shims for the back of the pads and such, however If I cant get them for some reason I always reuse the old stuff..clean it up with a wire brush and lubricate it a little with some caliper grease..The little "L" shaped metal "clip" I believe your talking about sounds like the wear indicator (placed at the bottom of the inboard pad)..If you can and if the new pads dont have one I would def. attempt to reinstall that...The manufacturer wouldnt have put those little metal clips there if they didnt serve a purpose... ...Since this is an 06' I'm assuming you have the front red SUBARU 4 pot calipers....FWIW I almost ALWAYS at least turn the rotors if not replace them when I replace a set of brake pads...