There are either 2 or 4 Cadillac disc brake calipers on all of their cars and SUVs. This is the end point of the hydraulic fluid's path, and the place it applies pressure to the braking system. The starting point of the hydraulic fluid pressure is at the master cylinder. The disc brake calipers fit over the rotors of the braking system that are connected to the wheels and are mounted on the spindle of the Cadillac. To help prevent metal to metal contact between the rotors and the disc brake calipers a pair of brake pads are used. The Cadillac disc brake calipers apply even pressure to the pads that are rubbing against the rotors of your car that will bring it to a safe and controlled stop. There are only a couple of occasion when the disc brake calipers need to be replaced. The first is when moisture enters the hydraulic fluid of your brake system. This can happen when the fluid in the reservoir is too low and air becomes trapped in the lines. This trapped moisture can pit the walls of the cylinder in which the piston travels, binding it and preventing the piston from applying pressure to the brake pads. The second reason the disc brake calipers of your Cadillac might need replacing is its age and the amount of use the car sees. Over many years of service a Cadillac will experience the failure of the polymer seals it has including the ones in the calipers. If your car is over 20 years old and not used much anymore, this part of your braking system should be checked for cracks in the seals so stopping it when you are using the vehicle will occur as expected.