Brake Vibration In The Mitsubishi Eclipse
The Mitsubishi Eclipse comes standard with front ventilated disc brakes. These brakes function by calipers pressing brake pads against the s...
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The Mitsubishi Eclipse comes standard with front ventilated disc brakes. These brakes function by calipers pressing brake pads against the spinning rotor to stop the vehicle. Over time, slight imperfections can cause a brake vibration.
Cause
Brake vibration is caused only by one thing: excessive run-out on the rotor. The run-out is the difference between the thickest and thinnest part of the rotor's disc. The Eclipse has a maximum rotor run-out of .002 to .003 inches, depending on the year.
Material Transfer
Material transfer is far and away the most common reason for excessive run out. This happens when friction material from the brake pad adheres to a section of the rotor, typically due to excessive rotor heat.
Repair
There are only two ways to repair excessive rotor run-out. The first way to repair it is to use a lathe to cut a small amount of the rotor's surface off and make it flat again. This can only be done if the disc thickness is at least .882 to .96 inches, depending on the year. If the rotor falls below that specification, the only way to repair the vibration it is to replace the rotor.