I just slapped on four new xd rotors with new pads that I got from a GD. When I am driving the car it is making a noise that sounds like when I was a child riding a bike, it sounds like when you put a plastic cup in your spokes of your bike and it made a noise we used to be so proud of, hopefully you know what I mean, but his is anything to be happy about in rotors. I have no clue what it could be.

I have never had a xd rotors before so I dont know if this is normal or if it wears out in time. I have since had it check by two different places and everything is put together correctly. Any clues as to what may be causing it? Frustrating.

 

the whirring sound is normal with slotted rotors from my experience...not sure about xd'd....

 

I put stillen xd rotors on my car and the noise was bad for awhile. It finally went away but it took some time and in my case the rear rotors took longer to break in. You will still have some noise even after they break in but usually only during hard breaking, but I am now able to stop on dime.

 

Yeah, the stopping is great, best set up I have ever had, just when the stereo is not on, its annoying.

 

I still get the noise on mine (at least 12k miles on them). Hasn't gone away and doesn't seem to big of a surprise that it happens. Probably very similar action as your bike example - the edge of the pad hitting the edge of the holes.

 

I put OEM pads and rotors on back few months ago, had to, rotors were about to die, they were originals at 95k. Now I am thinking of putting some kind of Brembo or other good ones to the front, with OEM pads. Does anyone think its a bad idea to mix the two, front and rear rotors?
Thanks

 

You can have slotted/cross drilled on the front with oem on the back if you like. No problems.

The humming everyone hears from using slotted/cross drilled rotors will not go away. It is just a by-product of the pad hitting the holes/slots in the rotor when the pedal is pressed.

 

I've had the same noise since i put on my Xdrilled/Slotted rotors. I don't mind it.

 

This is NOT happening when I am pressing the brakes, it is happening when the car is moving.