The U-shaped configuration of the Toyota disc brake caliper over the brake rotor makes it possible for pressure to be applied as a squeezing action to both sides of the rotor. This makes it possible for the friction being created to be the most effective when stopping your vehicle?s forward momentum. It is the task of the disc brake calipers to press the brake pads against both sides of the brake rotors in an even manner so a level application of force can be applied in the creation of the required friction to stop your Toyota. This is the braking component that converts the use of hydraulic pressure to mechanical motion. This mechanical motion in the disc brake caliper is the movement of the caliper piston out as the pressurized hydraulic fluid enters the cylinder. The disc brake caliper is made out of metal components except for the polymer seal that covers the area around the cylinder and the piston. This is the weakest component and the one that in time will develop a crack; causing a hydraulic leak to occur on your Toyota. When this happens, brake fluid will be seen on the pavement near the wheel and the disc will be covered along with the pads with brake fluid. The driver should also notice the brake pedal feeling softer with less sustained pressure in the braking process. If a blown seal on a Toyota disc brake caliper is not repaired, total brake failure for that wheel will be the result in a short period of time. If the owner of the Toyota can complete a brake pad replacement procedure, they can also replace the disc brake caliper. The only additional step is to remove the brake hose from the caliper and then bleeding the brakes.