strange noise on newly rebuilt brakes! - need advice

[Guest tom sixbey]

ok. as you can tell by my last topic, i've just gotten finished with a ton of work. My brakes are completely rebuilt with new pads and rotors, and i'm getting a strange metallic grinding noise from the rear whenever i get on the brakes. I put these things back together exactly the same way they came apart, and i've never heard this type of noise before. Its not a sqweaking sound, but more of a dull friction sound. I havent gotten to take the wheels back off of it yet, but i hope i'm not lathing anything! BTW the braking feel is excellent.. - its just this noise that's bugging me - any guesses?

[Guest tom sixbey]

i just checked all four wheels and no grinding anywhere. I've never used pads like these before, so maybe this is normal? everything is lubed, but i've got some missing shims (however it didn make this sound before).. still guessing..

[blueovalz]

What set-up are you using on the back?

[Guest tom sixbey]

hey terry - i've got stock rebuilt 79zx calipers with metal master pads, power-stop cross-drilled rotors and stainless lines.. i'm currently down at my parents house in texarkana, and i'll be driving home to memphis tuesday morning. If you're not at work, i could show it to you.

[blueovalz]

Dang it!!!! I'm headed out of town Monday. Oh well. Perhaps I'll be able to stop by in MEM some day when I'm up to see my boy. In the mean time, the only time I every had these symtoms was when the pad clips (that hold the pad in the bracket) were not fully seated, or improperly placed, causing them to scrap against the rotor. It was on the outside diameter of the rotor that was being rubbed.

[Guest tom sixbey]

hmm.. - i'll take another look at those when i get home... hey - i'm sure we'll cross paths in memphis sooner or later! - thanks for the help, and enjoy your trip!

[David K]

Speaking of the pad clips, when you put them back in over the pads, you push down on them towards the vented part of the rotor and they will make a snap noise. I put those clips in and didnt do this, and they made a scraping noise all day long. When i made sure they snapped in place, the scraping went away.

 

Does it sound more like a thin peice of metal scraping, than a grinding?

[Guest tom sixbey]

yeah - its a wierd thin metallic scraping sound, and not so much a heavy grinding. - i'll check those fron pads to make sure that the clips are pressed in - but the noise seems to be coming from the rear where there are no clips...

[JMortensen]

I think David is onto something. Check the edge of the rotors for scrape marks. That happened to me once when I didn't get the little anti squeal springs in correctly.

 

Jon

[Guest tom sixbey]

strangely enough, i thought that might be the problem, but i cant seem to find any scrape marks anywhere - even on the outer edge of the rotor. i'm gonna go out and recheck those clips right now though for proper installation... thanks for the replies guys - i'll let you know what it was when i find it

[Guest tom sixbey]

just got back from outside.. - front brake shims are good. it is definately coming from the rear. I am missing the rear shims, but the car never made any brake noise before on organic pads. - i'm gonna go to nissan and buy all of the shims in hopes that this will correct the problem (this being when i go to get some stock rubber tension rod bushings - thanks afshin!)