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Pads are bad. When you change them and the rotors, be sure to bed in the new pads.
 

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Did you resurface the rotors or change them to new ones before bedding?
 

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Discussion Starter #5
No i didn't do anything to the rotors besides wipe them off with a dry microfiber towel. i was planning on replacing my rotors at the next pad change in about 20-30k
 

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Anytime you change the pads, you need to either replace the rotor or resurface it or you WILL have problems like this. See the old pad wore down small grooves and reshaped the rotor. When you put the new pads on the shapes dont match up and thus you have abnormal wear patterns.
 

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Most likely, a large bit of something hard was imbedded in the pad there...or in the old one and you missed it when you added new pads. More likely the first, I guess.

Your pads might actually still be good; that one little groove isn't really going to affect your stopping power significantly.

Really small chance that a really small stone lodged between pad and rotor, but there's only a 5/1000" gap between them, so it either was a diamond, or just, as I said, a defect in the pad. You'll probably wear that through flat pretty soon...I wouldn't worry too much about it.
 

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Cool, i appreciate the help guys
I didn't say, but you should, of course, check the thickness of the pads, just in case the guy that said your pads are done is right. If he is right and you're down to metal, just at one point, you do need pads. But, if you can see the pad thickness and it's above a few mm, you've got time yet. Just look carefully just to be safe.
 

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Anytime you change the pads, you need to either replace the rotor or resurface it or you WILL have problems like this. See the old pad wore down small grooves and reshaped the rotor. When you put the new pads on the shapes dont match up and thus you have abnormal wear patterns.
Not entirely true. I just did my front pads. The rotors were flat, I had not vibration, just needed new pads (well, and in my case new calipers, but at 210K miles or so, I can't complain about needing some new parts!).

I believe that bmw rotors shouldn't be resurfaced, though I know many do. I'm not sure of the reasoning, beyond maybe the metal can get stressed if done too aggressively and that maybe BMW just wants to sell more rotors!
 

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No i didn't do anything to the rotors besides wipe them off with a dry microfiber towel. i was planning on replacing my rotors at the next pad change in about 20-30k
If the pads are still good for 20K to 30K, then the rotors are okay too. You need rotors with the next set of pads.
 

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also OP, rather than using a microfiber towel, just use brake cleaner on the parts. it will take care of anything that might have come into contact with the rotors/pads/etc while you were working on them. the cleaner will dry quickly too, so dont worry about that. oh, and make sure you have plenty of ventilation haha
 
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