Front 11 x 3 HD Brakes

[moreparts]

Does anyone know the interchange and/or part numbers for the front backing plates for the 11 x 3 front brakes for a 1970?  If they sell new replacements a source would be appreciated.  I redid mine and I'm getting a low speed clunk under light braking when the brakes are warmed up.  I suspect it may be the pads that need the lube being worn.

[Aloha Randy]

Check with me in about 4 months if you haven't found what you need. I am converting to Disc brakes on the front in the winter. I will have a full set of everything and I will not reuse it later.

[moreparts]

Thanks for the offer, Randy.  I may take you up on that!

[MoparLeo]

If you are talking about the backing plate pads that the shoe rides on, the common repair is to weld them to build up the height then file/polish back down to size. Do yours have grooves in them ? Takes a lot of miles to wear those pads down.

[moreparts]

Those pads are what I'm talking about, Leo.  I didn't see any grooves in there, but it it acting like they're hanging up on something.  I went through the brakes twice and everything is new and those backing plates are the only thing that's not. 

[MoparLeo]

Here  is a page from the 1970 Factory Service Manual. Do you have one ?

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Yup, I've had my service manual so long it's in tatters.  I've actually replaced the drums and pads twice trying to troubleshoot this.  I figure if it isn't those pads being worn it may be a bent plate. 

[MoparLeo]

Pad wear would be very obvious. I would probably remove and do a total inspection of the backing(mounting) plate and if it checks out, reinstall per the Factory Service Manuals instructions on torqueing them to specs.
Have you downloaded a service manual from this site yet ? That way you can look up what you need, print the page(s) and throw them away if you want after use. No more wear on your manuals...

[moreparts]

Pad wear would be very obvious. I would probably remove and do a total inspection of the backing(mounting) plate and if it checks out, reinstall per the Factory Service Manuals instructions on torqueing them to specs.
Have you downloaded a service manual from this site yet ? That way you can look up what you need, print the page(s) and throw them away if you want after use. No more wear on your manuals...


That is the baffling thing.  I didn't see any obvious signs of pad wear when I had the brakes apart.  Other than pulling them and putting on a replacement set of plates pretty much everything else is new.  And that's why I'd like to get some replacement plates, because if I'm going to take them off anyway I  may as well put some new ones on.  And yes, I've been know to print out those pages for reference as well.  Very handy with this sort of work.

[MoparLeo]

Are you using the proper type lube on the pads ? Are the shoes dragging on the pads surface ? If they are smooth and not worn why replace them ? Was  the noise there before the brake service? If not it must ne somewhere else. The shoes would be the likely culprit. Of course you could always do a factory disc conversion and also end up with much better brakes .

[moreparts]

Are you using the proper type lube on the pads ? Are the shoes dragging on the pads surface ? If they are smooth and not worn why replace them ? Was  the noise there before the brake service? If not it must ne somewhere else. The shoes would be the likely culprit. Of course you could always do a factory disc conversion and also end up with much better brakes .

I'm using a lube that does say it works for pads, and I'd guess it is because it's consistently coming from one side after both brake servicings.  When I first replaced the shoes and drums they were all worn out of spec.  When I noticed the noise, I noticed the shoes had cracks in them and I thought I had a bad pair.  Everything was under warranty so I got all new shoes and drums all around to rule those out.   I hadn't noticed that noise before the initial brake job. I do notice it after the the brakes are well warmed up from driving and under light braking pressure at low speeds.  I'm sticking with the drums because they've always been more than adequate for my driving and I like the originality with them.

[Filthy Filbert]

I can understand not wanting to remove them just to put the same ones back on; but to troubleshoot, can you swap only the plates from side to side, leaving everything else on the same side and see if the sound follows?

That would tell you if it's the plate or something else up front.  (maybe bad wheel bearings, loosening up tolerances after they warm up?)

[moreparts]

I can understand not wanting to remove them just to put the same ones back on; but to troubleshoot, can you swap only the plates from side to side, leaving everything else on the same side and see if the sound follows?

That would tell you if it's the plate or something else up front.  (maybe bad wheel bearings, loosening up tolerances after they warm up?)

That's a good idea, but with the work involved I think I'd rather chance it with some replacement backing plates.  They're generally pretty cheap.  If it were a drum or a shoe I'd definitely try that.

[Filthy Filbert]

Right.   It is a lot of work to verify the problem, then having to repeat the work to replace the part in question.   Might as well just do it all once.

[MoparLeo]

It is not hard to do a side to side drum swap. We did that often in the old days to chase a vibration.
If the problem only happens after the brakes warm up, think about this. What parts are warming up ? The backing plates ? or the drums and/or lining ?
Also steer clear of riveted lining. Cracked shoes are common at the rivet holes.
The same backing plates were there before the brake service and didn't make noise then so why now?
Lets say you replace the backing plates and the noise is still there ? What then ?