There are many ways to tell if your disc rotors need replacing. Some of these signs you will notice while driving, while others will need to be diagnosed by your local mechanic.
When braking if you hear a low grinding noise this can be an indication that your brake pads are grinding into your disc rotors which indicates your brake pads and/or disc rotors will need to be replaced. This grinding noise will become louder if not replaced.
While pressing down on the brake pedal if it feels like it is pulsating like you are pumping the brakes. One or more of your disc rotors will need to be replaced.
When braking if you come to an abrupt stop instead of smoothly your brake system is working as though the emergency brake is on.
Looking at your car’s dashboard, if the ABS warning light is on, it is an indication of a problem with your braking system.
Ridges on disc rotors
On the disc rotor’s surface deep groves, ridges, a burned appearance and brake dust are a sign to replace your disc rotors or have them machined by your local mechanic.
Machine Disc Rotors
All disc rotors have a recommended minimum thickness. Not all disc rotors need to be replaced; they can be machined and refitted. To see if your disc rotors can be machined, visit your local mechanic.
If any of these signs occur, visit your local mechanic to check over your braking system and keep you safe.