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Discussion Starter #1
Hello, First I want to thank Munki for his great strut removal instructions. They got me through my first strut change. That was hard work. Since I was doing my struts I put new pads in since mine were shot. Now they grind like they are metal to metal. It is terrible. And the one is gouging into the disc. I didn't replace the disc since it was still pretty good. Does the pad have to adapt to the disc? Has anyone else had this happen? Thanks.
 

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You usually want to seat them at first. You do this by hitting the brakes hard a few times right after you put them on. This is more to get any weird solvents off the pads, and I think it more beneficial to new rotors, so not a big deal in your case.

As you know it is the pad since nothing else has changed (right?) you are slightly better off. Maybe switch back to the old ones and see what happens? Or just take them off and reinstall?
 

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If you did not resurface the old rotors, you have created a situation optimal for squealing. The old rotors are scared/matched to the old pads. They grew old together. Now, you put new pads in place which have small differences in their surface compared to the old pads. This creates small vibrations which cause the squeal.

You can ride the new pads HARD until they quiet down. Ideally, you want to resurface your old rotors professionally. Alternatively you can resurface the rotors with fine sand paper until they feel smooth to touch.
 

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Discussion Starter #4
I believe the resurface is the answer. I took off the wheel last night and most of the noise/damage in on the passenger side. It looks like the new pads are slightly bigger than the old ones and are rubbing at the ridge created by the old pads. This sounds like large rocks being ground into the disc, like when your pads run out and it's metal to metal. I am going to try resurfacing the offending disc, it's only $10. If that doesn't work I am going replace the rotors. I am hoping my pads aren't runined because of the grit or something. Thanks for the advice. Shine on.
 

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Peter, both rotors must be machined(cut) , and equally, if at all. I just sand the rotor surfaces a bit using 36 grit emery paper.. I also measure the rotor as there is a wear limit(sometimes printed on the unit)..Optionial, IMO, is slightly chamfering the pad edges and an application of "anti-squeal" paste..

The "gouges and grooves" mean little, unless you are racing; there may be a little noise at first, within 1,000 miles the new pads will bed in.
Even since the disk brakes were introduced 40 or so years ago, people have complained of squeaks and squeals..
Improvements over the years have been many, thank goodness..
BTW, true hearing discomfort is listening to a true metal to metal condition at the disk brakes..
 

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There shouldn't be any metal to metal sounds or gouging of the rotors. You should check the pads to see if they are seated properly. When I put my pads on last year I didn't sand the rotors and they were fine. I did remove the lip from the outside edge of the rotor where the pad does not wear and it was still the original thickness. I was afraid the new pads would rest on the higher part of the rotor and take a long time to bed. Sanding the edge of the pads should help minimize this.

The purpose of the breakin period is to get a uniform coating of the pad material transferred to the rotors. The theory goes that if this coating is not uniform, it can feel like the rotors are warped, even though they are not. Stopping while the breaks are hot and before they have been bedded will allow more material to transfer to one location.
 

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Discussion Starter #8
Riding that edge seems to be my biggest problem. I would sand that ridge down but the grit from that seems to have caused my rotors to get rughed up a good bit. I may try that sanding first. It does look like the pad is sitting good otherwise, just that ridge. Thanks
 

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Discussion Starter #9
Here is the biggest laugh you will have all day. My grinding came from a break pad put in backwards. There were two of us working on it and we still put it in backwards. Though I think it had a lot to do with the fact that we had spent all weekend working on the suspention. Thanks for all you helpfull advise anyway.
 

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PETER S said:
Here is the biggest laugh you will have all day. My grinding came from a break pad put in backwards. There were two of us working on it and we still put it in backwards. Though I think it had a lot to do with the fact that we had spent all weekend working on the suspension. Thanks for all you helpful advise anyway.
Unbelievable !

This is something all men on this board felt to be impossible.

No wonder there was so much noise !
I just hope the pads/rotors are not ruined.
At the dealer we used a "handy-sander, 36 grit, and just broke the sharp edge, a chamfer of 1 to 2 mm. This was done on VW pads; I do not recall doing anything with the SAAB pads. They would "squeak" no matter...
Many things were tried to eliminate brake noise, most attempts did not work.
I think the application of a red plastic paste may work...

BTW, the rotors will wear down after 50 to 150K miles; many feel it is a waste of time to machine them; as before, the minor ridges and grooves do not hurt anything except, maybe, racing and rallying.
Warpage is a different story; this is a PITA and may affect the brake performance a bit..
 
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