What is the Standard Thickness of Car Brake Discs? Check Here!

Disc brakes have a very crucial function in a car's braking system. By using disc brakes, the speed of the car can be stopped quickly and steadily. For this component to function properly, the standard runout of the car's disc rotor must always be considered. So what is the correct runout standard? Let's find out the answer here!

Standard Runout of Car Disc Rotors

As explained earlier, the disc rotor functions as a speed controller for the vehicle in the braking system. The disc rotor is considered to have a better function than drum brakes. Disc rotors prevent the car from skidding easily when braking.

For the disc rotor to function as it should, it must meet the standards. To prevent the car from swaying when braking, the runout standard for the right disc rotor must be 11.02 mm square. Meanwhile, for the left disc rotor, it must be 11.04 mm.

The runout limit for the disc rotor itself is 12 mm, with a rework limit of 11.04 mm. If the disc rotor is too small or too large, the performance of the braking system will become less optimal.

How to Check the Thickness of Car Disc Rotors

After you know the runout standard of the car's disc rotor, you also need to know how to measure the thickness of the disc rotor to ensure it always meets the specified standards. Here’s how to check it.

1. First, measure the disc rotor part

Continuous use of the car sometimes makes drivers forget about the condition of the brake pads, whether they are worn out or not? If they are worn out, the performance of the car's braking system becomes less optimal.

Therefore, you need to check the thickness condition of the disc rotor. For the measurement process, you can use a caliper or micrometer to ensure the measurement results meet the specified standards.

2. Listen for any squeaking sound when the car is braking

For the second checking method, you can pay attention to the sound that occurs when the car is braking. If you hear a squeaking sound from the car, it can be confirmed that the condition of the disc rotor is starting to wear and thin. A worn disc rotor can increase friction between the braking system components, resulting in a squeaking sound.

3. Check the brake fluid level

Next, you can check the level of your car's brake fluid. As you know, brake fluid functions as a pressure transmitter from the pedal to the brake caliper. Brake fluid is a fluid that can adjust itself according to the container or reservoir.

To determine whether the brake fluid level has decreased or not, you can check it at the reservoir. If the brake fluid level decreases and is below the normal limit, it indicates that the brake pads are starting to wear. This happens due to the decrease in the thickness of the disc rotor affecting the thickness of the piston and caliper clamping.

4. Remove the brake pad part

For the next checking method, you can remove the brake pad part. To remove the disc rotor part, you must remove the front wheel before loosening the bolts on the disc rotor. Next, lift the caliper assembly so that you can take out the brake pads. If the brake pads are still thick, you will be able to see the line on the center of the brake clearly.

Thus, some information regarding the standard runout of car disc rotors and how to check the standard thickness and runout of the disc rotors. If you feel less confident to perform the checks independently, it is best to seek assistance from a qualified mechanic by visiting the nearest Daihatsu workshop. There, your car will be checked and serviced professionally using competent automotive tools.