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  #1  
Old 09-06-2010, 06:04 AM
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Squealie Brakes

After i bought my 84 300D, the front brakes (bendix) started squealing a bit, so i changed the pads. Squealing kept getting worse, so I added shims behind the pads with brake quiet and changed the rotors. No help, just kept getting worse. Changed the pads again and put on fresh rebuilt calipers, still no help, and im losing my mind. What else could it be??

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  #2  
Old 09-06-2010, 07:31 AM
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Maybe its time to replace the brake hoses too. Thats how i got rid of the squeeling on my rear brakes.
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  #3  
Old 09-06-2010, 07:41 AM
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The hoses are really the only things that havent been done. Really think that could cause squeal?
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  #4  
Old 09-06-2010, 09:22 AM
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what brand pads are you using? what construction?
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Old 09-06-2010, 09:48 AM
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I think the first change i used Textar. This time I tried the Mintex, both from Autohauz.
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Last edited by jkw0219; 09-06-2010 at 10:14 AM.
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  #6  
Old 09-06-2010, 10:09 AM
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Go with ceramic pads! I made the mistake of buying the Mintex pads on my 82' 300TD and they made a lot of noise, not to mention a lot of brake dust! My mechanic said "Well no wonder! You bought the cheapest pads they make!"
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Old 09-06-2010, 10:18 AM
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I would second the suggestion to replace hoses... I had the squealies on my new-to-me 190D, and I had to do pads, rotors, calipers, and hoses to get everything quiet again.

Kurt
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Old 09-06-2010, 10:19 AM
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Any recommendation for ceramic brand and where to get them? The noise is making me nuts.
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  #9  
Old 09-06-2010, 10:55 AM
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Quote:
Originally Posted by gastropodus View Post
I would second the suggestion to replace hoses...
In that case, perhaps you could explain the "cause and effect" relationship between brake hoses and noisy brakes. I am having a difficult time connecting those "dots."
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  #10  
Old 09-06-2010, 11:01 AM
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Quote:
Originally Posted by tangofox007 View Post
In that case, perhaps you could explain the "cause and effect" relationship between brake hoses and noisy brakes. I am having a difficult time connecting those "dots."
I've read elsewhere in the forums that brake hoses are multiple layer, and that the inner layer can break down. This can have the effect of creating a "one-way valve" where your foot pressure pushes fluid to the caliper, but then the inner layer collapses against itself trapping pressure on the caliper side of the hose defect. Just the theory I've heard...

Kurt
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  #11  
Old 09-06-2010, 11:33 AM
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Quote:
Originally Posted by gastropodus View Post
I've read elsewhere in the forums that brake hoses are multiple layer, and that the inner layer can break down. This can have the effect of creating a "one-way valve" where your foot pressure pushes fluid to the caliper, but then the inner layer collapses against itself trapping pressure on the caliper side of the hose defect.
The one way valve effect is certainly a real possibility. But I don't see how it would cause the typical brake squeal.
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Old 09-06-2010, 11:50 AM
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Quote:
Originally Posted by gastropodus View Post
I've read elsewhere in the forums that brake hoses are multiple layer, and that the inner layer can break down. This can have the effect of creating a "one-way valve" where your foot pressure pushes fluid to the caliper, but then the inner layer collapses against itself trapping pressure on the caliper side of the hose defect. Just the theory I've heard...

Kurt

mm, happens a lot, especially when people use locking pliers to crimp the rubber hose shut when working on the caliper...

If your hoses have had this done, or are 10 years old, change em, they are cheap maintenance.
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  #13  
Old 09-06-2010, 12:14 PM
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Brake noise is caused by high frequency vibration,this is why some cooper grease on the back of pads and on the anti rattle shims stops it,it soaks up the vibration.

Check the fit of the pads also at the bottom where they sit on the caliper and at the top,sometimes the pads back plate has a rough edge instead of smooth and this causes them to stick or pass noise on.

The disc can also pass noise if there is no copper grease or equivalent between it and the hub.
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  #14  
Old 09-06-2010, 04:41 PM
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I slathered Disc Quiet on the back of the pads both times i changed them, helped none. Matter of fact, when I changed the pads the second time, the Disc Quiet was still there on the old pads, so Im pretty sure thats not the source, or else it would have worn through making metal to metal contact.
The double hose is interesting, but even if it traps pressure against the caliper, how would this cause squeal?
My only option is to try the ceramic or organic pads I guess.
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  #15  
Old 09-06-2010, 05:19 PM
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Cut a thin piece of brass shim 12 - 15 thou and place under the pad. Cut the strip long enough to allow a 1/2" bend over each end so the shim won't slip out and just the width of the backing. Let us know if this works for you.
Squeal is caused by the pad grabbing and letting go, an up and down motion in the caliper. reduce the space for this motion and the squeal should go away.

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