The braking system may be a complex unit in modern vehicles. he components of the system must have strict requirements, Otherwise, it’s hard to stop a moving car. It is difficult to replace brake disc or brake pads for you, It is so “easy” for professional mechanics.
Correct understanding of the brake service can save time and money. In this article, We will discuss the basic brake repair and the steps of replace the brake.
What is the braking system?
The braking system uses friction to slow down the vehicle. When the brake pedal is pressed, the brake fluid from the main cylinder is pressurized and delivered to the caliper. Then, the piston of the brake clamp presses the brake pads to the brake rotor side (also called brake disc) to slow the vehicle down.

The brake system consists of:
- Brake rotor(Brake disc)
- Caliper and Caliper bracket
- With this brake clamp bracket are the sliding pin and hardware
- Brake booster
- Front/Rear brake pad
- Brake line
- ABS pump(Anti-lock brake)

Depending on the vehicle, also have drum brakes. The drum brake has a brake shoe, wheel cylinder, regulator, and other linkage devices.

How many brake pads and rotors are in one car?
There are 4 or 8 brake pads in one car. Usually,4 in front and 4 in the rear. There are 2 or 4 brake discs, 2 in front and 2 in the rear. But it depends on the OE status of the vehicle, Some of the vehicles has drum brake with OE status.
How long do brake pads last?
The general rule is 30000-50000 km. Of course, the driving style also affects the life of brake pads and discs. A more active driver may hit the brakes more violently and more frequently than a conservative driver. So driving habits are the biggest factor that affects brake pad replacement.
How do I know when to replace my brake pads?
Voice-listening
When you step on the brakes and hear the metal worn brake discs piercing, it is the sound made by the brake pad alarm indicator. It means that your brake pads have been worn out enough, We suggest you go to the car repair shop as soon as possible, so as not to affect your braking distance.

Looking
The brake pads wear to a certain extent, and the brake pad alarm indicator on your dashboard will come on. At this time, I hope you can ask a professional repairman to replace it as soon as possible, in order to let you later produce a misunderstanding

Check frequently
Brake pads have a certain thickness. When stepping on the brake, friction occurs between the brake pads and the brake discs, and the thickness of the brake pads becomes thinner during this process. The new brake pad thickness is 15 mm. If the brake pads are only a third in thickness. In other words, it is only 5 mm. Then there is no doubt that the brake pads need to be replaced.

By feeling
The feeling of relying on your own brake feet. Because the brake pads were used for a long time later, you feel like the brake system is slow when you hit the brakes, the brakes are also relatively light force. Because the brake pads become thinner after the car is used for a long time. Now, you should quickly go to the repair shop to find a professional repairman to check the brake pads, replace the brake pads if necessary
How long do brake rotors last?
The brake discs last for 50,000 to 70,000 km. Driving style will determine the lifetime of the brake disc. Maintaining a good driving habit will lengthen the service life of your brake discs.
When do brake discs need to be replaced?
Grooving
It will show the surface grooves after long time to use brake disc long, it is easy to produce abnormal brake sound after changing the new brake pad. If the brake disc wear grooves deep, It can lead to weak brakes or even no brakes when the brake disc thickness is less than the specified limit thickness. It’s very dangerous. Because at this time, even if the piston of the brake sub-pump reaches the maximum stroke, still can not press the brake pads onto the brake disc. So we suggest that you go to the repair shop as soon as possible.
Brake disc jitter
- When the vehicle travels at a high speed, to enable the vehicle to quickly stop the continuous braking, it causes the vehicle braking system temperature, deforming of the brake disc.
- When installing the new brake disc, the original dust impurities can not clean, which caused the brake to shake after replacing the new brake disc.
- The new brake disc is not balanced by the factory. Here is a video of us doing a dynamic balance for each brake disc.
Thickness
According to the use of their vehicles and the feeling of braking, we will check the thickness of the brake disc irregularly. When the brake disc thickness is less than the minimum thickness, we suggest you go to the garage or ask a professional mechanic to replace a new brake disc as soon as possible.
How to replace brake pads and rotors?
- Drive the vehicle to the station and lift it to remove the tires
- Remove the brake pliers, fix the bolts, and remove the calipers
- Take down the old brake pads from the calipers, return the caliper piston to the original local with a dedicated tool, fixed the calipers, prevent the calipers from falling then drag the brake oil pipe
- After fixing the caliper, remove the brake disc fixing bolt with the wrench and remove the brake disc
- Clean the hub unit contact surface and the caliper holder guide groove with fine sandpaper or special tools
- Finally, install the new brake disc-caliper bracket- -the new brake pad-brake clamp-tire in turn
What do I need for a brake job?
- New Brake pad
- New brake rotors
- Car jacks and jack brackets
- Sleeve set (for assembling calipers, caliper support, etc.)
- Lug nut wrench or Impact with impact sleeve (do not remove the lug nut)
- Torque wrench (Tighten bolts to correct specification)
- Brake piston return tool and brake clamp hanger
- Brake oil
Matters are to be noted after replacing the brake pad and brake disc.
After we replace the new brake disc and the brake pad, the contact surface of the brake pad and the brake disc often does not reach the optimal contact state, And only sufficient and correct running-in can make the disc, the piece to achieve the state of fitting to each other, so as to provide the best braking experience.
①Find the right road section
Before the run-in begins, we need a suitable road section, and find a section with less traffic flow to run in. It is better to grasp the speed of the vehicle, and also can ensure the safety of all people.
②Standard run-in process
Adjust the seat, flip the seat belt, and accelerate the car to 50 or 80 km / h with a slightly relaxed brake pedal, drive the car from 50 km / h until you stop. Or slowly slow down from 80 km / h to 30 km / h, speed up after completion, and repeat the operation. There’s no need to keep an eye on the speed watch, you have to see the road.
③Run-in should be gradual
The braking interval can be more than 30 seconds for brake cooling, otherwise, continuous braking will cause the braking system to overheating.
④Repetitive operation
The repetitive operation, repeat at least 20 times or more times, preliminary run-in is basically completed.
After completing the above run-in operation, the brake disc and pad still need about 300-500 kilometers (calculated according to the general urban road conditions) to achieve the best braking performance. During the run-in period, try to avoid heavy braking or intense driving. Otherwise, it will increase the running-in time, affect the braking effect and produce abnormal braking noise and other problems.
How long does it take to replace brake pads and rotors?
A complete replacement brake disc job may require 30 minutes to 2 hours for a professional mechanic or brake specialist. During braking work, factors such as rust and corrosion can slow down the mechanic. Some new and luxury cars require special tools to press the caliper pistons back. These additional steps will increase the braking working time
How do I find the right brake parts for my car?
Replace the aftermarket product brake pads according to your vehicle OE status, especially if the brake pad OE formula is related to your later change of the brake pad formula. If the formula is too different, it will make noise, it can bother you when you drive. Higher-quality brake pads can reduce brake wear and extend the service life of the brake pads
Be sure to check each component you purchase. some vehicles have different brake pad styles and sizes
Always compare the brake pads and brake discs for the appropriate friction material and dimensions
Some brake pads are somehow mounted in the vehicle. Make sure the old brake pads are in the same direction as they fall off, to ensure that the new brake pads operate in the same way
How can you take care of your brakes?
1. Avoid sudden braking
Emergency braking is especially very damage to the brake pads, so brake slowly when driving, or use the dot brake to brake, it wear of the brake pads is relatively smaller
2. Reduce the frequency of braking
In ordinary driving, to develop the good habit of reducing braking, let the engine brake reduce the speed, and then use the brake to further slow down or stop. Driving can reduce more gear to achieve deceleration
3. Check the brake pads and brake discs frequently
When the vehicle has traveled 40,000 kilometers or more than 2 years, the brake pads are more worn. Please check it out carefully and regularly, and check if the thickness of the brake pads is reduced to the minimum limit value, if yes, please change the brake pad. Then measure the thickness of the brake disc, lower than the minimum thickness of the brake disc, which must be replaced as soon as possible. Under normal driving conditions, the brake pads are checked once for every 5,000 km traveled, not only to check the remaining thickness but also to check the state of hoof wear, the degree of wear on both sides is the same, whether the return is free.
4. Position the wheels regularly
When the vehicle has a deviation and other problems, position the vehicle in time, so as not to vehicle tire damage, and it can cause excessive wear of the brake pads on one side of the vehicle
5. Watch out for the sound of the brake pads
If you hear the sound of a grinding iron sheet after braking normally while driving, it means that the brake pads have been worn to the brake disc, the brake pads must be replaced immediately, and the brake disc damage must be carefully checked
6. The replacement of the brake pad should pay attention to the running-in
After the vehicle changes the new brake pads, be sure to apply a few more brakes, to eliminate the gap between the shoe and the brake disc that caused by the first foot brake, in order to avoid accidents. In addition, it is necessary to run for 200 kilometers to achieve the best braking effect, and the newly changed brake pads must be driven carefully.