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For 1990-2009 cars only

Disc Brake System Description and Operation CSV HSV VXR8

Type B Disc Brake System

The Disc Brake System Consists of the following components:

Brake Pads

Apply mechanical output force from the hydraulic brake caliper to the friction surfaces of the brake rotors.

Brake Rotors

Use mechanical output force applied from friction surfaces of the brake pads to slow rotational speed of the tyre and wheel assembly.

Brake Caliper

Applies correctly aligned hydraulic pressure against the brake pads forcing contact between the friction surfaces of the brake pads and the brake rotor.

System Operation

Mechanical input force on the brake pedal is converted to hydraulic pressure, acting on the brake fluid through the master cylinder, booster assembly, ABS module and hydraulic brake lines to the brake calipers. The force is converted from hydraulic pressure, to mechanical force and is applied from the caliper pistons to the brake pads, forcing the friction surfaces of the brake pads and brake rotors to come into contact, slowing the rotation of the wheel and tyre assembly.

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.