The life expectancy of the Kia disc brake pads is determined by the aggressiveness of the driver and the smoothness of the surface on the rotor where the friction is applied. When a Kia owner is told they need a brake job performed on their vehicle, it is the disc brake pads on the front wheels that will be replaced. The rear brakes may either have pads or brake shoes; used in the drum style of braking system. The disc brake pads come in a set of four; an inner and an outer pad for each side. Unlike brake shoes that have a smaller one that should be placed in the front with the larger one in the rear, the pads are identical and are interchangeable on your Kia unless they have a special clip for a wear sensor. The Kia disc brake pads are located in the calipers which are mounted on the rotors. They are made of a material that is softer than the metal rotors so when contact is made, the pads wear out but the rotors are not damaged by this contact or friction. This material can be asbestos or carbon fiber. Each time the brakes are applied a small amount of the material the disc brake pads are made from will be removed in the form of dust. This dust should never be breathed in due to health concerns. There are two noises that can be generated from the disc brake pads on your Kia. A high pitched squealing noise is the pads vibrating in the caliper when the brake pedal is being pressed. This situation can be fixed with the application of anti squeak on the back side of the pads. If a grinding noise is heard, then the pads are worn out and the backing plate is coming in contact with the rotors cause damage to them.