For 1990-2009 cars

## Disc Brake System Description and Operation LWB SWB

### System Component Description

The disc brake system consists of the following components:

Brake Pads: Applies mechanical output force from the hydraulic brake calipers to friction surfaces of brake discs.
Brake Discs: Uses mechanical output force applied to friction surfaces from the brake pads to slow speed of tyre and wheel assembly rotation.
Brake Caliper Anchor Plate: Provides mounting for the hydraulic brake caliper and secures the brake caliper firmly in correct relationship to the brake disc. Enables a sliding motion of the brake caliper to the brake pads when mechanical output force is applied and the reaction of the brake caliper anchor plate pulls the outer pad against the disc. The forces of the pads on each side of the disc are therefore equal.
Brake Caliper: The brake caliper incorporates either twin (front) or a single hydraulic piston (rear), each with a fluid seal. When hydraulic pressure is applied, a mechanical output force on the piston applies the inner pad against the disc. When the hydraulic pressure is released, the piston fluid seal/s retracts the piston/s a small amount, allowing the moving parts to relax sufficiently for the pads to remain in close proximity to the disc without dragging. Adjustment for wear is automatic.

### System Operation

Mechanical output force is applied from the hydraulic brake caliper pistons to the inner brake pads. As the pistons press the inner brake pads outward, the brake calipers draw the outer brake pads inward. This allows the output force to be equally distributed. The brake pads apply the output force to the friction surfaces on both sides of the brake discs, which slows the rotation of the tyre and wheel assemblies. The correct function of both the brake pad and brake anchor plate is essential for even distribution of braking force.