For those of you with slotted/cross-drilled rotors...

Discussion in 'OT Driven' started by Slappy3243, Aug 11, 2008.

  1. Slappy3243

    Slappy3243 Ello?

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    I replaced my stock rotors and pads yesterday on my '05 GTO with Hawk performance ceramic pads and DBA 4000 series slotted rotors. The install went normally and is as easy as changing out the pads and rotors on an f-body. However, there is a clicking noise now when the brake pedal is applied at speeds above 40 mph or so. It sort of sounds like a card in a bicycle wheel when you were a kid. I have done some research and most people say that it is simply the nature of slotted rotors and that the pad makes noise when going over the slots. I am hoping this problem will go away with pad break-in. The sound slows down with the rotor and it certainly seems like it must have something to do with the pad and the slots. I just thought I would have heard more complaints from people with this pad/rotor combination. Any opinions or thoughts on how to correct this problem or do I just have to live with it? Thanks.
     
  2. vudoodoodoo

    vudoodoodoo New Member

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    Yes, replace them w/ solid discs. :o
     
  3. Slappy3243

    Slappy3243 Ello?

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    Not gonna happen. Pretty much the only place to get blank discs for this car is from the dealer and they charge almost as much per rotor as these were but are shitty in quality and will warp quickly.
     
  4. vudoodoodoo

    vudoodoodoo New Member

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    I'm pretty sure you can get Brembo OE replacements online somewhere...
     
  5. SilverTurtle

    SilverTurtle New Member

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    iRotors might be able to sell you Brembo blanks for the GTO... they sold me Brembo slots for the 2 f-bodies that I have them for

    slotted rotors do tend to make that noise, though... mine on the '01 and '02 Z28s make them and its not really a problem, as I just turn the stereo up to compensate for it :)
     
  6. Slappy3243

    Slappy3243 Ello?

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    Nah, iRotors just makes a slotted rotors for the '04 GTO which is a different size than the '05 cars. Shopping for this car can be a pain in the ass. Rotors for the F-body are all over the place since they are so common. Getting rotors for my Hawk has never been a problem. Tirerack has Brembo slotted rotors for my GTO but no blanks and Tirerack carries a ton of Brembo shit. Thanks for the help though. I am hoping the sound gets better over time.
     
  7. Slappy3243

    Slappy3243 Ello?

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    I searched and may have came across them at some point but they were just about as expensive as the DBA slotted ones I got so I thought getting the DBA slotted rotors would be the better choice. I am going to break them in more and see what happens.
     
  8. deusexaethera

    deusexaethera OT Supporter

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    I have slotted rotors -- mine have three big slots instead of six or eight thin slots, too -- and I definitely know what you're talking about. The noise will go away for light braking once everything's broken-in and happy, but it will always thrum a bit during heavy braking.

    They're really good for detecting suspension wear, too -- when I put mine on, the car felt like it was falling apart every time I stopped. New control arms fixed that problem.
     
  9. Slappy3243

    Slappy3243 Ello?

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    Thanks! The car is at the dealer right now for an ABS light that comes on randomly :ugh:. It started coming on way before I changed out the rotors and pads so I didn't break anything when I did the install. But fuck it, the car is under warranty and they will fix it! It also has a slight vibration in the steering wheel at about 60 mph which comes and goes. I had the wheels and tires balanced several time but it didn't fix it so maybe they can look at it.
     
  10. deusexaethera

    deusexaethera OT Supporter

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    A slight vibration that comes and goes is probably runout on the hubs, i.e. the wheels are wobbling side to side very slightly, and depending how they're rotated compared to each other at any given time, the vibrations might cancel out or they might add up.

    When you installed the brakes, did you sand the hubs and the backs of the wheels to make sure there was absolutely no grit on them? Even a piece of sand caught between the hubs, rotors, and wheels can throw off the runout enough to be noticeable with sensitive modern steering.

    If you did all that, then the only other thing I can think of is the rotor hats aren't the same thickness all the way around. Try rotating each rotor 72 degrees (one lug nut) clockwise until the vibration goes away, then mark the rotor position with a Sharpie.
     
  11. GammaRadiation

    GammaRadiation Active Member

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    "warping" is often a cause of the pads, not the rotor itself.
     
  12. Corz

    Corz ha ha! snikt

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    I'll check with my work tomorrow and see if I can get you a pair of blanks.
     
  13. Slappy3243

    Slappy3243 Ello?

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    Very true. The pads will leave behind residue causing the warping sensation. Honestly, the OEM rotors that came stock on my '05 GTO were not that bad except they easily rust and the stock pads fade.
     
  14. Slappy3243

    Slappy3243 Ello?

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    Thanks man. I mentioned the runout on the hub issue to the tech at the dealership but he said he never heard of it causing that problem before on the GTO (surprising right?). He said the hub runout could cause my vibration though so who knows what the fuck they are going to do to my car.

    When I did the brakes, I cleaned all of the surfaces with brake cleaner and paper towel. I did not sand or scrub the hub faces with a wire brush since I figured that would be enough. Apparently, the GTO is extra sensitive to shit like this unlike my cars in the past so I didn't give the hub that much detail. I know that is a mistake now. There was still some dirt left over on the hub face when I put the rotor back on so that could be my issue. However, I notice the clicking sound becoming less apparent the more I drive the car which is a good sign. From what I am reading, the hawk ceramic pads are very hard and will cause the clicking sounds on slotted rotors until they are fully bedded in (upwards of 500 miles or so).

    Thanks for your help. I will update this thread when I get my car back.
     
  15. Slappy3243

    Slappy3243 Ello?

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    PM me when you get the information so no details get in the public eye. I appreciate the help. :)
     
  16. deusexaethera

    deusexaethera OT Supporter

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    I don't know for sure if the GTO is as sensitive to hub runout as my Passat is, but given that it's supposed to be a "performance car", the suspension is not likely to be designed to give a nice soft feel, which means you'll notice shit like this more often.

    If the tech is any good, he'll just spin the wheels with a feeler gauge right next to the edge of the rim and see if the gap changes size as the wheel spins, before he starts doing anything that actually costs money.

    I have EBC ceramic pads, and they took over 1000 miles to fully break in. On the other hand, they last damn near forever and they don't shit all over your rims.
     
  17. Slappy3243

    Slappy3243 Ello?

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    I just gone done talking with the Pontiac service department. While a history of the ABS code was stored, they could NOT fix it because they tested the wheel sensor (that is what the code pointed too) and it was working just fine. So the manager basically said unless they can prove that it is broken, they cannot do anything. I explained to the manager that this is unacceptable since this is a major safety issue. When the light comes on, I have neither ABS or traction control. He said he would call the district manager or whomever he had to call and he was still refused. He felt bad that he couldn't replace the sensor or hub and I understand that. GM is not letting him do it basically. GM would rather risk my life then replace a damn part. I know GM is hurting right now but that is ridiculous. Does anybody here have a number I can call or an email address for GM corporate? He said to try to contact them but didn't have the number on him. This is going to get resolved one way or the other. Thanks for the help.
     
  18. deanh8

    deanh8 New Member

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    Risk your life?
    hahaha

    Usually codes that throw that kind of symptoms are (well 90% of the time) wheel sensor related, either something had some some moisture in it, corrosion in it, or something simple. (and usually work their way out over time once the moisture drys up or whatever the problem is).

    Only effect it will have is your ABS will be off and TC will be disabled like you said. Sounds like your the one who is risking your own life by not being able to drive a non abs/tc equipped car.
     
    Last edited: Aug 15, 2008
  19. Slappy3243

    Slappy3243 Ello?

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    :ugh: It is a safety issue. Innovations such as ABS and traction control are made for a reason. What if I am driving along in the rain, have to brake hard and the ABS fails suddenly? There is barely enough reaction time to stop let alone realize my ABS has failed and start pumping the brakes like it is the fucking 1980's. The problem has not worked itself out and it has been doing it for two years.

    It is funny that you think I am the one risking my life though. What is the point of having traction control and ABS then? GM would be so fucked if a crash was caused by a faulty ABS sensor. That is why I am even more baffled as to why they won't fix it because it the end, it all comes down to their asses. People like you are funny though. You are right though, I should just man up and ignore the WARNING lights and sounds and pretend everything is ok :ugh2:.
     
  20. deanh8

    deanh8 New Member

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    If its been doing it for 2 years, why did you just take it to the dealer now?

    GM made that stuff for people who cant drive. I drive a GM car with almost the same computer control system as you, I (Purposely) took out my ABS fuse and my ABS light, trac off light are both on and my magnasteer is all disabled. I daily drive it like that and I have no problems. I hate the stupid ABS kicking in and the traction control slamming on the brakes like I dont know what the fuck im doing.
     
  21. Slappy3243

    Slappy3243 Ello?

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    I reported it now because it is becoming much more frequent. It is used to be so rare that I would forget it happened.

    Good luck with your insurance company after you get into an accident and they find out that you disabled your ABS and traction control. I purchased this car with the intention of having everything working correctly. If something is to go wrong which is the case right now, I am paying for a warranty that should cover it. It is not something I should have to fight for.

    For whatever reason, you enjoy removing advanced safety features in your car. That is up to you. I however, have no problem with letting technology give me a helping hand when it comes to safety. Did you disable your airbag too?
     
  22. deusexaethera

    deusexaethera OT Supporter

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    The car will still stop even if one of the wheels doesn't have a functioning ABS sensor. If one of the two wheels on each brake circuit senses a skid, the ABS pump takes control of both wheels. It does need to get fixed, but you're not going to flip over and blow up in the meantime.

    Anyway, tell them to replace the sensor anyway and just pay for it. If that still doesn't help, then you know it's a bigger problem; otherwise, you're out a couple of days' pay and the problem is gone.
     
  23. Slappy3243

    Slappy3243 Ello?

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    Actually, that is incorrect. When the ABS light is on and is not functioning, it does not work at all. I tested it and verified it with the dealership. When the ABS light is on and I slam on the brakes, all of the wheels lockup. There is no pumping feel in the pedal from the ABS feedback at all, nothing. I am not worried about flipping over in the short-term but again, it is just the principle of the matter.

    Also, I paid for a warranty as part of the purchase price. There is no reason that I should have to pay for repairs on a car with 25,000 miles on it.
     
  24. deusexaethera

    deusexaethera OT Supporter

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    I agree that you shouldn't have to pay for repairs under warranty, but it really comes down to how badly you want to get it fixed.
     
  25. Slappy3243

    Slappy3243 Ello?

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    Very badly. The Service Manager is calling on Monday after he speaks with district again to express my concerns.
     

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