Disk brake pad shims?

Disk brake pad shims? - 05/04/14 10:17 PM

First of all, thanks everyone who answered my question on the rotor bearing preload adjustment. That's been taken care of- the rotor is on, so I'm moving on to the next step...

Next question - I've noticed that with the set of caliper pads I got, there is a set of shims with adhesive backing on them. They came in a white plastic pouch with vague instructions advising to apply the shims to the backs of the pads w/o removing the adhesive backing and checking the alignment- afterwards the backing can be removed and the shims applied to the back of the pads. It fails to say of course WHAT this 'alignment' is, and there is no mention of this in my '69 Charger FSM for the disk brake pads (although it is referring to the K-H/Bendix calipers).

My questions are:

1) What alignment is this referring to? I've never seen something like this, even on a non-Chrysler car, and

2) Do I need to worry about using them at all?

Again- thanks for any advice!
David

Posted By: nomore65BelvJim

Re: Disk brake pad shims? - 05/04/14 10:52 PM

Did they specifically call them shims?
I did the brakes recently on my F body wagon which has the same brakes as your donor. It came with no "shims" or anything like what you describe.
Could just be anti-rattle/squeal stuff.

Posted By: David_Trimble

Re: Disk brake pad shims? - 05/04/14 11:44 PM

I took another look at the 'instructions' - it definitely refers to them as shims. They seem to be flat pieces of metal, no coating on them other than black paint on one side and a adhesive on the other-so if they're anti-rattle I can't imagine them being very suited for it. If that's their only function I suppose I can leave them off for the time being, and if the brakes get noisy then I could always go ahead and pull the pads and install them...

Quote:

Did they specifically call them shims?
I did the brakes recently on my F body wagon which has the same brakes as your donor. It came with no "shims" or anything like what you describe.
Could just be anti-rattle/squeal stuff.

Posted By: nomore65BelvJim

Re: Disk brake pad shims? - 05/05/14 12:18 AM

Heres the page from the manual for the disc brakes. It doesnt mention shims just the use of the anti squeal compound

Attached picture 8134048-100_3875a.jpg

Posted By: David_Trimble

Re: Disk brake pad shims? - 05/05/14 12:48 AM

Quote:

Heres the page from the manual for the disc brakes. It doesnt mention shims just the use of the anti squeal compound

Interesting..... I doubt these shims are replacements to the anti-squeal compound.... if the Diplomat's FSM makes no mention of the shims then I'll probably be ok in not using them. But now I'm wondering if I need to get a tube of that compound and apply some to the back of the pads...

Posted By: nomore65BelvJim

Re: Disk brake pad shims? - 05/05/14 01:16 AM

I didnt use any on the 76 Aspen wagon and they are fine so far with over 1000 miles.

Posted By: RapidRobert

Re: Disk brake pad shims? - 05/05/14 02:48 AM

It's a substitute for anti squeek lube. The alignment is you want it between the metal portions of the adapter/caliper that the pad metal backing plates touches as it is that contact that squeals. Yes mock it up to see where it goes then slap it on there. You do not have to use em & if your pads are quiet you're good. & if they ain't then take em out & stick on the pads. My sliders were incredibly noisy till I judiciously used some DBQ sparingly on the back on areas of contact as needed

Posted By: David_Trimble

Re: Disk brake pad shims? - 05/05/14 03:01 AM

Quote:

It's a substitute for anti squeek lube. The alignment is you want it between the metal portions of the adapter/caliper that the pad metal backing plates touches as it is that contact that squeals. Yes mock it up to see where it goes then slap it on there. You do not have to use em & if your pads are quiet you're good. & if they ain't then take em out & stick on the pads. My sliders were incredibly noisy till I judiciously used some DBQ sparingly on the back on areas of contact as needed

Hmm- a wierd substitute for anti-squeek lube- I wouldn't have ever thought that's what they were for :/

So I'll just hang onto them and if they do get noisy I can just slap them on there as you say.

Posted By: RapidRobert

Re: Disk brake pad shims? - 05/05/14 03:40 AM

Quote:

Hmm- a wierd substitute for anti-squeek lube- I wouldn't have ever thought that's what they were for :/

Oh I agree & I cant say I've even seen that but there is no reason to shim pads so they cannot be anything but a novel antisqueak trick likely to avoid comebacks from unhappy owners upset with the noise & blaming the pad otherwise the pad mfr would not have gone to the trouble and expense of including them with the pads. It would be nice tho if they would have included good instructions that properly explained their purpose for the consumer

Posted By: west

Re: Disk brake pad shims? - 05/05/14 05:01 AM

I've never understood why they are called anti squeal when they have nothing to do with the contact area of the pad, which is where the noise comes from. I think they serve more as an anti vibration device.

Posted By: drew72

Re: Disk brake pad shims? - 05/05/14 01:54 PM

Quote:

I've never understood why they are called anti squeal when they have nothing to do with the contact area of the pad, which is where the noise comes from. I think they serve more as an anti vibration device.

Exactly. That is where the squeal comes from. Manufacturers have been using these anti squeal shims for years. 20 or more to my knowledge. They are packaged in pads that are known to have problems. They should definitely be installed.