Depends on how it's been driven and how far the pads wore down. It's not a mileage thing.How often do you need to change the break rotors on you automobile?
Typically break rotors are considered a catastrophic failure....BRAKE rotors should be replaced when they wear down to below thickness specifications...How often do you need to change the break rotors on you automobile?
Thet are BRAKE rotors.
You don't, unless there is a problem like severe wear. Machining can be done if they are not too bad.