What Function do Rotors Serve?

You can find a set of brake rotors in every car with a disc brake setup. What are rotors, and why are they important parts of your Volkswagen’s braking system? Read on to find out.

What are Brake Rotors?

If you remove one of the wheels on your Volkswagen, you’ll see a brake rotor. What is it, exactly?

Rotors

Also called a brake disc (or sometimes rotor wheel), a rotor is a cast iron or stainless steel disc that’s between 9 and 16 inches wide. Some are held in place for convenience during manufacturing by a rotor retaining screw. A caliper and a pair of brake pads are installed over the rotor. The whole setup is covered by a wheel, which is attached to the hub and rotor by lug studs and nuts. The lug studs and nuts firmly clamp the wheel and rotor to the hub.

Why Your Car Has Rotors

The rotors on your Volkswagen are a key component of the braking system. Because your rotors are attached to the hub, they rotate along with the wheel. As explained below, the calipers act on the rotor to slow the car.

How a Rotor Works

It takes a lot of power to stop a vehicle, and a set of OEM Volkswagen rotors does the trick. How can a few small metal disks stop a two-ton vehicle, though?

The answer: heat and friction.

When you press down on your brake pedal, the caliper squeezes inwards and presses the brake pads against both sides of the rotor. The contact between the brake pads and the rotor creates friction. The friction converts the energy of a moving car into heat and stops the wheels from turning. This in turn stops your car. With a good set of brake rotors and pads, you can stop your car in a matter of seconds.

Not All Rotors are Created Equal

OEM VW Rotor

Your rotors are arguably the most important components of your Volkswagen’s braking system. In fact, they’re so important that the quality of your rotors pretty much determines your car’s stopping power.

If you want to maximize your Volkswagen’s stopping power, your best bet is making sure your car has a set of OEM rotors in good shape. You can outfit your car with a set of aftermarket rotors, but there’s a good chance they won’t perform as well as OEM ones. It’s because aftermarket rotors aren’t built to OEM specs. They may be the wrong size, or they may be built with the wrong materials. As a result, these rotors wouldn’t work optimally with your calipers and brake pads. You can read more about the differences between OEM and aftermarket brake pads here.

Some VW owners hesitate to buy OEM brake rotors because they can be pretty expensive. It’s understandable. After all, dealerships mark up their prices by a lot, sometimes even 30%.

The good news is that you can buy genuine OEM VW rotors at discounted prices online. Take our website, for instance. We offer genuine OEM VW parts, including rotors, at reasonable prices. Here are two examples:

  • Part No. 561-615-601-A (rotor that fits 2014-2018 Passats) usually costs over $60 at dealerships, but you can get it from us for $45.56.
  • Part No. 5C0-615-301-B (rotor that fits 2012-2017 Beetles, GTIs, and Golfs) usually costs over $100 at dealerships, but you can get it from us for $77.71.

You’re free to contact us with questions about your rotors and how they work. We’re always happy to discuss all things rotors!