BRAKING NEWS: Ford Disc Brake Rotor Types
They are a major part of the disc brake system and is its namesake. The disc brake, or brake rotor, comes in different types and flavors and in this Brake Tech article we’ll show you the major types that you’ll see most in OEM and aftermarket disc brake systems.
Up first is the solid disc brake and it’s a one-piece of metal, usually cast iron in OEM applications. There are two-piece solid disc brakes as well but those are usually found in aftermarket applications. Being a single, solid piece it can be very easy to see when it is ready to be replaced as the surface begins to wear out. However, while being a single piece and simple makes it very inexpensive, it is easy to overheat in high performance applications.
Next is the vented disc brake rotor and you can tell that you have a vented disc by simply looking at the rotor head-on. You’ll see that the front and rear surfaces of the rotor are connected by little slats. Those slats are actually veins that allow air to flow through and cool the rotor and why most front and aftermarket rotors will be of a vented type. They are more expensive to produce but the cooling generated by the veins will more than make up for this in front and high-performance applications.
In very high-performance and aftermarket performance brake rotors, you’ll notice that the surface isn’t always smooth. The surface will either have holes or slots cut into them. These slots and holes are designed to remove the gasses that build up from the heating of the adhesive that bonds the brake friction material to its packing plate. Cross-drilled rotors will use the flow of air in the rotor veins to evacuate those gasses, however it does come at a cost of rotor surface strength and longevity.
Slotted rotors, on the other hand, will not only remove those gasses but also retain the strength and help remove some of the non-burnable debris from the friction material. Both cross-drilled and slotted rotors are directional so be sure to confirm with your rotor manufacturer on the correct direction before installing a set. You’ll also see cross-drilled and slotted rotors in some applications and are a “best of both worlds” solution.
Finally, you’ll see multipiece rotors that have a rotor and brake hat as two separate pieces that are held together by bolts and locking nuts. These are usually seen on very high-performance applications in both OEM and aftermarket. This can save some money in the long run as you’ll only have to replace the rotor surface when it wears out or want to increase the size of the rotor face. However, the initial purchase can be fairly expensive.
