Brake Rotor Replacement: What Is a Rotor and What Does It Do?
September 7, 2016
By Benjamin Hunting / Originally Published August 16, 2016 / National Automotive Parts Association /
Brake rotor replacement is something every driver eventually faces, and it helps to understand a little about how this component fits into your car’s braking ecosystem so you can make smart choices when talking to your mechanic. Brake rotors are some of the most durable parts on your car, but over time the stress of daily driving takes a toll, even on steel.
What Is a Rotor?
On all modern cars, the front brakes, and usually the rear brakes, make use of a rotor and pad design. The pads tighten around the rotor (which is also called a disc) when you push down on your brake pedal. The pressure comes from fluid in the master cylinder that activates the caliper housing each set of pads. The friction that ensues transforms your car’s forward momentum into heat, which is dissipated through the rotor and pad into the air around the wheel.
How Do Rotors Wear Out?
Given the amount of stress they are under brake rotor replacement is not an uncommon repair. Still, rotors hold up for tens of thousands of miles before they typically need to be swapped out. Over time, the metal material coating the disc simply wears away due to friction, which is the most common reason for brake rotor replacement. Sometimes there can also be issues with the rotor warping, which is the term used when it’s no longer perfectly circular and flat. This leads to uneven contact with the brake pad and translates into vibration as well as reduced stopping power.
What Are Your Brake Rotor Replacement Options?
There are three main types of brake rotor replacement choices. Blanks — that is to say completely flat and smooth discs — are the most common, and are recommended for the majority of drivers. If you’re looking for extra performance, you can opt for either slotted rotors, which have angled slots carved into their surface, or drilled rotors, which have holes drilled all the way through. Some rotors even have both. Slotted units are designed for more aggressive bite as well as to channel the gasses and heat generated by forceful braking away from the rotor, while drilled discs achieve a similar result through their holes.
It’s worth keeping in mind that slotted rotors will chew up brake pads much more quickly, while drilled rotors are typically not as strong as standard blanks because of the material that is removed during the drilling process. Sticking with smooth blanks is your best bet for longevity and performance in most situations on the road.
For more information on brake rotor replacement, chat with a knowledgeable expert at your local NAPA AUTO PARTS store.
Photo Credit: Destroyed brake rotors by interiot (CC BY-SA 2.0).
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