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Hey guys-

I already posted in Stop, Drop, and Roll, but thought this might be a better place for me question and i'm trying to get my car back before the weekend. I just got my car car lowered on eibachs and new rotors/pads/lines installed. So the problem is that the shop called and said there seems to be a lot of vibration under heavy braking. I went down to check it out, drove it, and it seems pretty fine. Only got a slight vibration once. Everything is aligned and balanced, no bent rims (stock). From what I experienced, and from what the shop told me after driving it multiple times, it seems to have corrected itself.

Is this possible?

They got things pretty drity, and there is a lot of gunk still on the pads/rotors from their install. Is there any kind of break-in period? I don't want to walk away saying that it is fine when something might be wrong.

So anyway, my question is that is it possible things worked themselves out after putting a few miles on the car? And i'm getting black smears on the rotor, is that just from the install and will it go away?

edit: I've been reading and searching around, it seems that my problem is that there is pad material deposited on the rotor (the black smears). Did they shop not break the new pads in correctly and completely? I know there are products to help remove this stuff, but do i need to make that step already? or will some more wear on the rotors/pads take it off.

Thanks in advance for the help guys, +rep for anybody who can give me a good answer/related experience.
 

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Installed new pads, rotors and ss brake lines, if the shop installed it properly and bleed the system.....the brakes have to bed down (settle down). But if there is still vibration after a couple of days of driving and braking, take it back to the shop.
 

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If the pads weren't bedded, at all, then you will have to bed the pads yourself. try doing 5-6 60-20 SLOW DOWN's do not stop, then do 4 40-20 slows, again, DO NOT STOP, or you'll transfer pad-material to your rotor and it'll be "warped". Depending on the pads, and fluids, you may experience brake fade, so don't go and do this on a busy street. Also, do this in rapid sucession, one right after the other. Once you are done, drive around for 10+ minutes w/o stopping and it'll cool the pads and rotors. You may smell some something burning, its normal coz its the adhesive burning away as you are heating the brakes up. Doing this will also burn/clean off pad material ON the rotor now, which you proably have.
 

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This is what I follow for Bedding:
When bedding the pads, be very careful as the brakes will not work to well until you are done. The way that I bed brakes is as follows:

I do my bedding on the open road when there is little traffic. Drive at about 50-60 mph and apply the brakes, dragging them while giving the car gas to maintain the speed. Drag brakes for about 10 seconds and release. Drive for about 1 minute to allow the brakes to cool, then drag the brakes again for about 20 seconds. The brakes may begin to smoke, stink and you might feel a bit of green fade at this point but that is normal. Drive for another minute to cool things off again and drag the brakes for 30 seconds. You should defiantly be smelling the brakes now and feeling some green fade. Be careful at this point as now you will not be able to stop too well if you had to. Drive about two minutes and repeat the process. You might have to repeat this up to three times. You can tell when the pads are bedded when you don’t feel the onset of green fade any more. Be careful not to overdo the bedding process or you could glaze your brand new pads or even warp or crack your rotors.

Note that these are general bedding instructions. Some pad manufactures have very specific bedding instructions that you should follow. Call the maker of your pads to find out what is the best for them.

When returning to the pits or home, be sure not to apply the parking brake until the brake are completely cool as this might warp the rear rotors. In fact it is a good idea to take a cool down lap if you are at the track to allow your brakes to cool off before coming into the pits. Heat soak after hard running can damage the caliper seals and warp the rotors.

To bed the brakes on the track, simply drive carefully at about 80%, anticipating the green fade and maybe dragging the brakes lightly on the straits. When you feel green fade coming, back off and drive without braking for about ½ lap to let the brakes cool. Repeat until you don’t get any green fade. Never start a race on new unbedded pads. All of your spare pads should be bedded beforehand. Even if you have bedded pads, if they are freshly bedded I would still be cautious about green fade for a few laps especially until you get a good feel for the bedding procedure with your favorite brand of pads. If you are new to bedding, you may not bed your pads completely and still get some green fade, a nasty surprise if you are not anticipating it.

Many of the new generation Carbon pads do not need to be bedded much. When running those I simply bring them up to operating temp while allowing myself some extra run out just in case, before I go all out. On the street, I would run them through one bedding cycle to burnish them in. Consult with the maker of your Carbon pads though, as some of them may have some different bedding procedure than what I am describing.

Harder, high temperature pads usually have an overall lower coefficient of friction even when they are in their ideal operating temperature. Because of this you can expect having to push on the brake pedal much harder with them installed unless you go to a bigger brake system with more pad area. Softer, lower temperature pads generally have more initial bite and require less pedal effort but they will fade much quicker.

Through proper selection of brake pad material and careful bedding you should be able to reduce pad fade to a manageable level except in the most extreme racing conditions.
 

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Hey guys, I too NEed Help!! I just changes my rotors and pads and I got my car back a couple days ago and noticed the vibrations when I hit the brakes at about 60-70mph. I also had my calipers powdercoated. could It be that I also need to brake every thing in? I bought my rotors and pads on Ebay (don't know if it was a mistake) but anyways I am not sure what to ask my mechanic or what I should be checking for. Please Advise I don't want to F*ck up my baby.
 

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sometimes rotors come untrue and need to be turned. ebay rotors... some are good, some are bad. esp if you went really cheap. i have irotors and they are holding up nicely. my friend didn't, got some cheap no name crap that now has cracks on every outer hole on every rotor.

if you bedded the brakes properly and still get a vibration, take the rotors to brakemasters and they'll turn them for $10 a piece. if the problem persists, further diagnostic is needed. let us know and we'll go from there.
 

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Don Corleone, Thanks for the info.. I will check to see if I need to turn the rotors. I looked at the discription on ebay and they're supposed to be "plug and play" but every one I spoken to so far has told me I might just need to turn them ... I won't beable to bring my car into the shop till tuesday, do you guys think i will be fine driving it one more day?? I usually have heavy traffice in and out of work so I don't go too fast and I only notice the problem when I go 60mph or more and brake. What do you guys think?
Oh By the way I got the brembo rotors (X/S) and ceramic pads don't remember the brand on the pads, but they were off the same auction on ebay. (...I know , I know I sould have done my research and gotten the BBK, especially after the cost of powdercoating :/ but nontheless the calipers look seeeeeet :)
 

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you'll be fine for another day. from what you're describing it doesnt sound like something that would cause an accident, just something that is annoying and wearing your pads a bit more than normal.

i'm from the school that thinks that bbk on this car is not necessary unless you are a track regular. i myself have irotor rotors, oem pads, stoptech ss braided brake lines and i know my rotors are more for aesthetics than performance.
 

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Hey guys I checked with the guy i bought my rotors from to see why I am having the vibration problems, and he told me it was normal because the rotors are zinc plated and that the vibrations was caused by the pads rubbing it off. He told me I shouldn't worry too much and to take it easy until they are broken in. Hope this info helps some off you guys or gals out there :)
 
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