question about weird brake noise
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MBWorld Fanatic!
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C63 AMG P30 *EuroCharged*| Porsche Cayenne | Buell XB9SX
question about weird brake noise
when i do hard braking, my brakes, or at least i think it's my brakes, make a weird noise ... sounds like a humming sound, like when you drive over a bridge that has one of those metal grating surfaces, or when you drive on grooved pavement. i also get a "funky" feel through the pedal. "hard braking" = 60-30 braking downhill, or 60-30 on a freeway. i still have 60% pad left in the front and 90% rears. anyone know what this could be? glazing? also, my tires are nearing the end of their useful lives, although not below the wearbars yet. wondering if the weird feel i am getting is related to poor rubber contact with the road. anyone have any ideas?
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Joined: Apr 2011
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From: Portland, OR
99 c43 / 99 ml430
i have that right now and think its the rotors being worn down towards minimum thickness combined with maybe uneven brake pad material on the rotors. I dont like the sound either.
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From: PDX
1999 C43, 2008 P30 E63, 2014 SQ5, 2024 Model Y Performance
I have the exact same sound, I believe hoontastic is correct regarding having to do with the minimum thickness of the rotor.
Definitely not tire related as I have new tires...
Definitely not tire related as I have new tires...
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From: Canada
eclectic assortment of cars
What do you mean by 'funky' feeling in the pedal? Does it judder, and you get feedback through the pedal? That could mean the rotor is warped slightly. If so, you can machine them down a tad to make them true again. There are plenty of people who are against this, but I've done it before on other cars and have had no issue, as long as you are still within the thickness guidelines, and don't machine too much off. For what is a pad clamping on a rotor other than machining but with a much less abrasive material? Beats buying new rotors, especially on C43/E55/CLK55 because they're so expensive.
Removing the wheel and looking at the rotor, is there a ridge on the outer edge of the rotor? If so, that is a sign that the rotors are nearly used up. There are minimum thickness values for them. I can't recall if it's stamped onto the rotor or not though. You need a special set of calipers to measure rotor thickness.
Here's MarcusF's page on brake specs:
http://www.marcusfitzhugh.com/CLK/DIY/brspec202.html
Removing the wheel and looking at the rotor, is there a ridge on the outer edge of the rotor? If so, that is a sign that the rotors are nearly used up. There are minimum thickness values for them. I can't recall if it's stamped onto the rotor or not though. You need a special set of calipers to measure rotor thickness.
Here's MarcusF's page on brake specs:
http://www.marcusfitzhugh.com/CLK/DIY/brspec202.html
Thread Starter
MBWorld Fanatic!
Joined: Sep 2005
Posts: 3,165
Likes: 59
C63 AMG P30 *EuroCharged*| Porsche Cayenne | Buell XB9SX
What do you mean by 'funky' feeling in the pedal? Does it judder, and you get feedback through the pedal? That could mean the rotor is warped slightly. If so, you can machine them down a tad to make them true again. There are plenty of people who are against this, but I've done it before on other cars and have had no issue, as long as you are still within the thickness guidelines, and don't machine too much off. For what is a pad clamping on a rotor other than machining but with a much less abrasive material? Beats buying new rotors, especially on C43/E55/CLK55 because they're so expensive.
Removing the wheel and looking at the rotor, is there a ridge on the outer edge of the rotor? If so, that is a sign that the rotors are nearly used up. There are minimum thickness values for them. I can't recall if it's stamped onto the rotor or not though. You need a special set of calipers to measure rotor thickness.
Here's MarcusF's page on brake specs:
http://www.marcusfitzhugh.com/CLK/DIY/brspec202.html
Removing the wheel and looking at the rotor, is there a ridge on the outer edge of the rotor? If so, that is a sign that the rotors are nearly used up. There are minimum thickness values for them. I can't recall if it's stamped onto the rotor or not though. You need a special set of calipers to measure rotor thickness.
Here's MarcusF's page on brake specs:
http://www.marcusfitzhugh.com/CLK/DIY/brspec202.html
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Joined: Mar 2008
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Dynocomped C43K, 08 X5
I have crazy sqeeky sound from my brakes. While my impedence on brake noise level is probably higer than usual, its so embarassing when I catch attention of other driver.
When time comes I will follow the same root as Mr. Moneyone.
When time comes I will follow the same root as Mr. Moneyone.
