Your vehicle’s brake system has one job – stop your vehicle. But it takes several key components to deliver that singular end result.
To bring a vehicle to a halt, three things are necessary: leverage, hydraulic force and friction. Leverage is supplied by the driver’s leg pressure and the brake pedal. The pedal is connected by levers and rods to the back of the power booster. The power booster uses either engine vacuum or a hydraulic pump to multiply and transfer the force of that leverage to the master cylinder. The master cylinder is the heart of your vehicle’s brake hydraulic system. It uses applied leverage to force a reservoir full of brake fluid through valves, steel lines and rubber hoses into hydraulic calipers and wheel cylinders. That hydraulic pressure is then used to help create friction.
For example, disc brakes use a hydraulic caliper fitted with brake pads to grab a spinning disc (or rotor). Drum brakes, on the other hand, have a hydraulic wheel cylinder that pushes a brake shoe against the inside of a spinning drum. Either design involves highly engineered parts and precise movement. The more force a driver applies to the brake pedal, the greater the stopping force that is applied at the wheels.
In addition to this primary braking system, most of today’s vehicles utilize an electronic Anti-lock Brake System. Using electronic sensors and high pressure pumps, under certain conditions, your ABS system can measure vehicle speed, wheel slip and brake force. Then it actually pumps the brakes for you during an emergency stop.
That’s why it’s essential to be proactive about testing overall brake components. And to know whether a brake component needs simply to be serviced or totally replaced.