The frequency of replacing brake rotors depends on several factors including the type of vehicle, driving conditions, and maintenance habits. In general, brake rotors should be replaced when they become too worn, damaged, or warped to provide sufficient braking performance.
Brake rotors are typically measured for thickness during regular brake pad replacement or during routine maintenance. If the rotors fall below the manufacturer's recommended thickness, they should be replaced. It is also important to replace warped or damaged rotors, as it can cause brake pulsation and compromise braking effectiveness.
However, there is no specific mileage or time interval for replacing brake rotors, as it varies widely. Some rotors may last for several tens of thousands of miles, while others may need replacement sooner depending on driving habits. Regular inspections by a qualified mechanic can help identify when it is time to replace the brake rotors.