You step on the brake pedal, and your vehicle comes to a halt. Brake pads – it’s a term that might sound familiar to you, but you’re not quite certain how it all works together.
Let’s start our tour of the brake system at the wheel. Remove the tire from the vehicle, and we can see your brake set up. The disk is your brake rotor. The caliper hooks around the rotor. If you were to remove the caliper, you would be able to see where the brake pads sit. The caliper cradles the brake pads and squeezes the pads to the rotor when activated, but we’ll get into that later.
Inspecting the brake caliper, you’ll find a rubber brake hose that leads to a steel brake line. It’s through this line that your brake fluid flows. Speaking of brake fluid, if you’re familiar with anything under your hood, you may recognize the brake fluid reservoir.
But how does it all work to stop your vehicle on the road?
When you step on the brake pedal, it activates a plunger-like device within the master cylinder – the piece which houses the brake fluid reservoir. This pushes the brake fluid out of the reservoir and through those steel brake lines. This creates a buildup of pressure on the caliper, specifically the piston (or pistons) in the middle of the caliper. The piston extends out and pushes the brake pads against the spinning rotor. When the rotor’s spinning is stopped, the wheel stops turning.
Once pressure is taken off of the brake pedal, the plunger in the master cylinder eases off of the pressurized system, and the brake fluid is then allowed to flow back into the reservoir. That causes the piston to retract back into the caliper, releasing the rotor and allowing it to spin freely once more.