In the engine compartment, above the master cylinder, there is a brake fluid expansion tank that supplies brake fluid to the entire brake system.
The hydraulic booster accumulates part of the vacuum produced in the engine intake system. Then, as needed, the force of pressing the brake pedal is increased through the booster valves.
The front and rear disc brakes have what are called floating caliper calipers. In a floating caliper, only one piston is required to press both brake pads against the disc.
The handbrake acts on the rear wheels via a cable. On models with rear disc brakes, brake drums are additionally installed in the brake discs to operate the handbrake. This is necessary because disc brakes are not suitable as a parking brake.
When cleaning the brake system, brake dust is released. This dust is dangerous to health. Therefore, you should take measures to avoid inhaling it.
The manufacturer produces different types of pads for different models of cars. Therefore, it is recommended to install only brake pads recommended by BMW.
It is recommended that when purchasing brake pads, you also purchase brake pad wear sensors, as the sensors installed on the vehicle may also be worn out.
Work with the brake system requires accuracy and precise adherence to the instructions for its implementation. If you do not have experience in carrying out such work, it is better to carry it out at a service station.
Note: When driving on very wet roads, brake occasionally to free the discs from deposits. Although the water is thrown away from the brake discs by centrifugal force during driving, a thin film of silicones, rubber dust, grease and dirt partially remains on them, reducing the braking effect.
When parking the car after driving in the rain, especially in winter with special impacts on the road, it is advisable to stop the car by lightly pressing the brake pedal. Thanks to this, the brake discs are dried and will not corrode intensively.
After installing new brake pads, they need to be allowed to break in. During the first 200 Nm, sharp braking to a complete stop should be avoided.
Corroded brake discs produce shaking and noise that does not disappear even after repeated braking. In this case, the brake discs should be replaced.
Burnt dirt and clogged rain grooves on the brake pads cause scratches on the brake discs. This reduces the braking effect.
Caution: If the brake pedal travel varies when cornering, check the lateral runout of the discs on the outside diameter or replace the discs.