VARIATIONS
Rotors -- There are two types of discs, or rotors:
ventilated or solid.
Ventilated rotors are better than solid rotors because they have more surface area (two inside and two outside) from which to release heat. Because of this and better air circulation caused by the cooling fins in between, they cool faster than solid rotors do. Disc brakes should not overheat and fade even after heavy braking.
Calipers -- There are two basic caliper designs: floating and stationary. A stationary caliper has one piston mounted on each side of the rotor. A floating caliper has one piston mounted on the inboard side of the rotor. It slides inward to activate the outer brake pad.
Pads -- There are two types of brake pads, semi-metallic and non-asbestos. Semi-metallic pads are made of metal and last longer. They are usually used in high performance vehicles. Non-asbestos pads are made of an organic compound. Pads are either riveted or glued to the brake shoe. Riveted pads are better.
Previously, brake pads were made of asbestos but were discontinued for health reasons.
Wear Sensors -- There are three types of wear sensors:
- Audible sensors make a high pitched squeal
- Visual sensors activate a dashboard light
- Tactile sensors create a pulsation in the brake pedal (do not confuse this with ABS pulsation which occurs only during extremely hard braking)
If any brake sensor is activated, have the pads inspected immediately and replaced if necessary.
