Hello, welcome back to the Counterman Education Center. Stop! In this video, we're going to look at the different types of break rotors. There are multiple ways to approach this explanation based on the various characteristics of break rotors. For example, we could break it down by style. The original traditional hub rotor, where the front bearing hub and the rotor itself are all cast together. The bearing and the race are replaceable with this style. Now in the mid 1990s, this all changed with the advent of the hubless or hat rotor that has become almost the synonymous choice of manufacturers. Hat rotors were lighter in weight, less expensive and easier to manufacture. Since installation involves only sliding them off and on a sealed wheel bearing and hub assembly, service is clean and quick, making them popular with technicians as well. Another way to approach this question is to talk about what they're made of. Cast iron is the most common and affordable material. And from a practical standpoint of servicing the millions of everyday vehicles on the road, it's all we will likely see in our daily routines. These are cast iron because it's an inexpensive material that is incredibly durable and has excellent heat transfer properties, which is a main component of brake operation. Other materials can boast clean benefits when it comes to racing or performance, but they simply cannot match the longevity and economy of cast iron. Another way to explain the different types of brake rotors is to ask if they are vented or if they are solid. The difference between the two is vented rotors have an open space between the inner and outer surfaces, connected by veins that directly allow air to flow between them for better heat dissipation. Solid rotors are used primarily on small lightweight vehicles or in the rear only. Solid rotors are almost always used in the front and for heavier and serious performance vehicles they are used in the rear as well. But we're not there yet. You might also hear plain drilled slotted. Plain, also known as blank or smooth rotors, are the most common. And the surface of the rotor appears to be exactly as the name suggests. Drilled or cross drilled have a series of holes drilled in them that increase the cooling ability of the rotor. Slotted rotors have grooves cut into the rotor surface and they reduce brake fade by allowing gas to escape that can build up under the pad during extreme braking. They also tend to scrape the brake pad material and reduce glazing. Ground and slotted can benefit the braking on any car but longevity of the rotor pad is less. Are we there yet? Not quite. We still have coated and uncoated. The newer vehicles are more aerodynamic in order to improve fuel economy and that means there's less air flow through the wheels to dry out the rotors. This is where coding comes in. There are different types but it's simply a chemical coding that is specifically designed to prevent rust and corrosion. The coating gets worn off where the pads contact the rotor but it's especially beneficial in the veins and around the edges of the rotor. Here's just one more for the road. Most rotors are made of one piece of cast iron. However, two piece rotors, also called floating rotors, have a separate disc and bell or hat that are bolted together. The disc is made of cast iron and the bell is usually aluminum. The advantage is weight savings and the reduction of heat transfer into the wheel bearings. One of the biggest benefits is the disc is able to expand separately from the bell which can prevent cracking or warpage. When someone asks you to talk about the different types of brake rotors, there are surely a number of ways to slice and dice your answer. I hope this gives you a good foundation to educate your customers. We'll see you next time and thanks for watching.