Stock brakes. How many miles before issues started?

JARblue

This is only necessary if you install new pads that are composed of a different compound that the previous pads

As mentioned, the "warped" rotors are almost guaranteed to be just uneven pad deposits. You can have the rotors "turned" by any brake shop to remove the excess pad deposits and level the rotor surface for smoother braking.

From what I can determine, most of these scenarios are caused by improper braking habits, although an emergency maneuver can do it as well. My wife "warped" the rotors on our Z in less than 20K miles when she was daily driving it. When the Z became my DD, I fixed the issue and have since put over 50K miles on it with absolutely no shuddering or shaking under braking.

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