Another "my brakes make noise" thread :(

[bcar240]

this may be a fairly commonly answered question, but I couldn't find the proper search term(s) apparently and didn't find much. My brakes, about a week ago, started making a nasty scratching type noise, not squealing under braking. It is very loud, but intermittent, and can be heard even when I am not braking. It seems to be coming from the rear brakes, but they make the sound individually. Like sometimes it only comes from one side, something the other, sometimes both at the same time. It also seems to be set off by hitting a bump in the road or other jarring, but also can start at random for no apparent reason. The noise itself reminds me of a grinding wheel type sound. It changes with speed and goes away completely when I stop, and sometimes a very hard tap on the brakes will get rid of it too. After driving for a while, say 15-20 minutes, the sound seems to go away for the most part. I don't know the history of my brakes before the last 2 years, but other symptoms are telling me it is probably time for a thorough replacement. Seems to have no effect on braking performance though. I was just wondering if this is some sort of typical indicator of a certain part failing or what, I have a hard time imagining what would be making that sound. Thanks!

[FutureDRFTer]

is there a rock or pebble?

that happened to my friend and he got a nice groove in his rotor...

[bcar240]

I'll check on that in a few minutes when I'm out there. I live on a gravel road so it is possible, but it is weird that both sides do it. I was thinking about it some more and I was wondering if it was possible for there to be something wrong with the master cylinder or brakes lines that would cause too much pressure on the back calipers and make the pads drag on the rotors really bad.

I am about ready to swap to Z32 calipers in the front and was gonna do all 4 rotors and pads, so I am hoping that it is just old pads or something. Have worn out pads been known to have symptoms like this?

[S14toRPS13]

It's that metal clip on your brake pads scraping your rotors. It's time for new pads and probably new rotors too.

[240sxs13sleeper]

just wondering ...how much would rotors cost..and for slotted rotors too? thx

[AmoebAssassin]

Ebay special rotors cost me about 180 for zinc plated slotted rotors shipped (Z32 front S13 rear). So far they have held up fine.

BTW I agree with the worn brake pad diagnosis.

[bcar240]

word, that makes sense then I guess. A quick q for the caliper swap though, can I change the pads before it is installed in the car or does it need a little pressure to reseat the pistons or anything? Also, do you really need new shims or it that one of those change your oil drain plug every time you change your oil type thing? Thanks again.