Tech Toolbox: Brakes

Since the dawn of the automobile, technology has propelled us forward at an alarming rate. Larger displacement motors, more efficient transmissions, stronger differentials, and better tires for traction have fueled our unending need for speed. So how do we STOP?

Remember your high school physics class? Of course you do, but just in case, here is a quick refresher. Blaise Pascal, a French mathematician, discovered that fluids are not compressible and transmit force evenly in all directions. You may recall an equation called Pascal’s Law: Force = Pressure X Area. This is the basis for all hydraulic systems like your vehicle’s brake system.

The hydraulic brake system of your vehicle is made up of the following: master cylinder, brake lines, calipers and wheel cylinders. A master cylinder has two pistons inside that put pressure on the brakes as you put pressure on the brake pedal. The pressure produced by the pistons inside the master cylinder is transmitted through the brake lines and is applied to the calipers or wheel cylinders.

All modern vehicles have disc brakes on the front. Disc brakes are made up of a caliper that, when applied by brake system pressure, squeezes two brake pads against a metal disc called a rotor. The rotor is bolted to the axle with the same bolts holding the wheel and turns at the same speed as the wheel. This squeezing action produces friction and slows the wheel.

Some vehicles, especially trucks, use drum brakes in the rear. In a drum brake system, the wheel cylinder pushes two brake shoes against a metal drum that is bolted to the wheel and axle. This creates friction and slows the wheel.

In either system, the friction material on the pads or shoes wears off over time, and the pads or shoes need replacement. Drum brakes use a series of levers and springs and require periodical adjustment and cleaning. Also, the brake drums and rotors become warped or scored from constant heat cycles. A warped brake rotor or drum will cause your vehicle to vibrate when coming to a stop. These parts require precise machining with special lathes.

Does your vehicle have a brake vibration or squeal when coming to a stop? Come see an Everett Certified Service technician. We use the latest technology in brake lathes to match your rotors to your vehicle.

David Gibbs
Certified Service Technician
Everett Chevrolet Buick GMC