318Touring 40 Report post Posted September 10, 2012 (edited) This only happens on the right-rear disc, the pictures might be able to tell the story. Braking is smooth, no wobbling, no effect whatsoever on braking at all. I suspect it might be FOD (foreign object damage) caught between the pad and disc causing this. Pads still in very good condition, around 40000kms the OBC told me. I'm wondering what my best strategy is: a. Take the pads off and try to clean the surface of both pads and disc. Would this cause brake wobbling though? b. Leave it as is and replace pads and discs when the time has come. c. Replace pads and discs ASAP. TIA! Edited September 10, 2012 by 318Touring Quote Share this post Link to post Share on other sites
westy 614 Report post Posted September 10, 2012 Almost looks as though they've run the previous brake pads to the steel backing. How's the thickness of the disc? Quote Share this post Link to post Share on other sites
318Touring 40 Report post Posted September 10, 2012 Almost looks as though they've run the previous brake pads to the steel backing. How's the thickness of the disc? That might be true, however it seems that it had been looked after by Jeff Gray in Chch. I suspect they wouldn't cut corners. Also this is only on one corner not one axle. I don;t have the tool to measure disc thickness unfortunately. Quote Share this post Link to post Share on other sites
hotwire 352 Report post Posted September 10, 2012 If the face of the lining is ok- it is likely old damage (metal/ metal) as suggested. You wll need to have the disc thickness checked to see if it can be machined flat & still maintain minimum thickness. If this is possible - machine both discs & replace pads (regardless of wear left in them) If below min - obviously new discs required. Quote Share this post Link to post Share on other sites
dubman 39 Report post Posted September 10, 2012 can this be caused by the use of crappy brake pads? Quote Share this post Link to post Share on other sites
hotwire 352 Report post Posted September 10, 2012 ^^^ Could but they would need to be bloody hard, almost metal Quote Share this post Link to post Share on other sites
318Touring 40 Report post Posted September 10, 2012 Thanks fellas. Previous owner was older couple who had the car looked after by JG in Chch. This only happen on one wheel (RR). Would brake usage differ between the four corners of the car? Or differ between left and right side of one axle? Quote Share this post Link to post Share on other sites
westy 614 Report post Posted September 10, 2012 Would brake usage differ between the four corners of the car? Or differ between left and right side of one axle? Yup. Completely normal. Doesn't need to be much difference in wear (1/2 mm?) for one to hit the backing plate. Quote Share this post Link to post Share on other sites
swordfish 30 Report post Posted September 11, 2012 My girlfriend's E36 323i brake rotor looked exactly the same as this after metal/metal contact, and it was one side only too. The only difference, it was her front brake rotor. I've changed both rotors and pads for brand new OEM not too long ago (aprox. $300 GST incld). This usually happens when people in garage shops change rotors or pads on one side only as the other side seems ok at a time or by customer request to save money (without knowing that might cost them much more in the future if this kind of stuff happens). Quote Share this post Link to post Share on other sites
318Touring 40 Report post Posted September 11, 2012 Right! Once again thanks for your feedback. I might get a garage to see whether that can be skimmed. Seems that rear pads & discs cost around $250 ex UK. According to the OBC rear pads still have 41,000kms life on them. Quote Share this post Link to post Share on other sites
westy 614 Report post Posted September 11, 2012 If the thickness of the disc is still well over spec I'd take option 2. But then again, I am a cheap-skate mongrel. Quote Share this post Link to post Share on other sites
318Touring 40 Report post Posted September 11, 2012 (edited) LOL, I think disc quite ruined from the look and feel of it. The ridges are around 0.5mm deep, might have to be thrown away. Would be more economical to just replace them, DIY. I just need an impact driver to remove the bolt on the discs in case it's stuck. This crowd might even have them cheaper than ex UK ones Edited September 11, 2012 by 318Touring Quote Share this post Link to post Share on other sites
elmarco 56 Report post Posted September 11, 2012 I'm assuming it's for a BMW - if so you could try Paul at Milland. Pretty reasonable prices, and good to deal with. Quote Share this post Link to post Share on other sites
andrewm 236 Report post Posted September 11, 2012 My brothers subaru had this, suspected foreign matter damage aswell, rotors are so cheap anyway I replaced them and pedal feel improved a bit, didnt have to push brake pedal so hard. Quote Share this post Link to post Share on other sites
318Touring 40 Report post Posted September 11, 2012 Yup it's a bimmer (E87), and I haven't done anything yet. Now I know what needs to be done, it's easier to plan. Thanks again. Quote Share this post Link to post Share on other sites
_ethrty-Andy_ 2122 Report post Posted September 11, 2012 skimming them will be much much cheaper. should be around $20-30 at any engineering crowd on a friday afternoon. Quote Share this post Link to post Share on other sites
hotwire 352 Report post Posted September 11, 2012 Only if machining wont put them below minimum thickness. Also, discs best machined on vehicle so needs someone with an on car lathe Quote Share this post Link to post Share on other sites
318Touring 40 Report post Posted September 11, 2012 Anyone knows who does mobile service at Welly? Quote Share this post Link to post Share on other sites
_ethrty-Andy_ 2122 Report post Posted September 12, 2012 Anyone knows who does mobile service at Welly? Yes, call this guy (I'm copying from his card), i used him about 6 months ago, fantastic service. Kane Anderson Masterbrakes 027 444 0493 brakegrind@gmail.com looking at his card looks like he does drums too. i think it cost me either $20 or $40 per side, certainly was cheaper than i expected him to say when i called. Quote Share this post Link to post Share on other sites
318Touring 40 Report post Posted September 12, 2012 Thanks mate. I'll give him a try. Quote Share this post Link to post Share on other sites
BLACK DORIS 9 Report post Posted September 28, 2012 Thanks mate. I'll give him a try. How did this go? I just had bearing and break lines replaced. Found a similar issue only on the right front disc, minimal but would interested in getting a mobile guy in. Cheers Quote Share this post Link to post Share on other sites
318Touring 40 Report post Posted September 29, 2012 He's going to come in tomorrow (Sunday) morning. I emailed him and after a couple of weeks we managed to arrange for a time. I'll let you know, he said if it can be skimmed then both discs (from the same axle) needs to be done to avoid imbalance. Around $100? Quote Share this post Link to post Share on other sites
