The GMC brake disc is part of the assembly of brake components placed at each vehicle wheel that work in cooperation to produce the friction needed to stop your vehicle when you step on the brake pedal. Constructed of cast iron, the GMC brake disc provides the contact surface that the brake pads use to produce friction. The brake pads are moved into contact with the GMC brake disc by the brake caliper, one pad on each side, squeezing the GMC brake disc between them. The brake pads are lined with a friction material, helping them grip the GMC brake disc firmly to create friction that will work against the momentum of the wheels to stop the vehicle. The most common type of GMC brake disc is equipped with a number of fins between the contact surfaces, designed to dissipate the heat produced by the braking process. This style of GMC brake disc is standard in most vehicles. There are a number of custom GMC brake disc styles, engineered for higher braking performance. These can be especially good for vehicles that see harder use or high performance vehicles. The slotted style GMC brake disc is one custom style, made with a number of shallow channels in its surface to help shed the used friction material left by the brake pads more efficiently. Another custom GMC brake disc style is the drilled disc, with an array of small holes drilled through the surface to aid in heat dissipation. Our online catalog carries a selection of GMC brake disc replacements, both standard and custom styles, al at very reasonable prices. Ordering is always safe and easy on our secure site, or the expert customer service on our toll-free phone line will make it just as convenient.