Brake line
Carries brake fluid pressure from the master cylinder to each wheel.
Along the underbody from the ABS unit to each corner.
Rigid metal pipes handle most of the route; flexible hoses take over where the wheel moves.
A sealed hydraulic artery.
A soft pedal, fluid loss or corrosion on the pipes needs immediate inspection.
Pads and discs are measured wear items. Driving, environment and regenerative braking change wear; use the actual inspection limits.
Ordinary friction service differs greatly from carbon-ceramic replacement or hydraulic-controller work; obtain a vehicle-specific quote.
BMW routes lines through the DSC unit, which can modulate each wheel’s pressure on its own.
BMW models with hydraulic friction brakes; performance equipment and parking-brake design vary.