There are a few ways to tell if your brake pads are worn out:
1. Visual inspection: You can remove the wheels from your vehicle and inspect the brake pads. If the pads are worn down to less than 1/4 inch thick, they should be replaced.2. Squeaking or squealing noise: As brake pads wear down, the metal indicator on the pad will come into contact with the brake rotor, causing a squeaking or squealing noise.
3. Grinding noise: If you hear a grinding noise when you apply the brakes, it could mean that the brake pads have worn down completely and the metal of the rotor is rubbing against the metal of the pad. This can cause damage to the rotors and is a sign that the pads need to be replaced immediately.
4. Warning light: Some vehicles are equipped with a brake pad wear indicator light onthe dashboard. If this light comes on, it's a sign that the pads are worn and need to be replaced.
5. Vibration while braking: If you feel a vibration or pulsing in the brake pedal or steering wheel while braking, it could be a sign of worn brake pads.
It is good practice to inspect your brake pads and rotors every time you change your oil or get an oil change service, it's also important to have the brake system checked during your regular maintenance check up.
It's also a good idea to have a mechanic inspect your brakes if you notice any of the symptoms above, or if you suspect that your brake pads may be worn.
Also, Keep in mind that some of these symptoms can also be caused by issues with other brake components, such as calipers or rotors, so it's always best to have a qualified mechanic inspect your brakes if you notice any problems.