Disc Brakes System Description Front Wheel
The disc brake assembly consists of a caliper assembly, the rotor, and the lining assemblies mounted on the steering knuckle.
Applying the brake pedal causes the hydraulic pressure that moves the caliper piston. The piston then forces the inboard brake lining assembly against the inboard braking surface of the rotor. Increasing the force against the rotor causes the caliper assembly to move inboard. The outer brake lining assembly then contacts the outboard braking surface of the rotor. The force of the two lining assemblies provides the desired clamping action on the rotor.
Releasing the brake pedal relieves the pressure applied on the piston. The square cut seal on the piston relaxes and the seal allows a running clearance between the brake lining assemblies and the rotor.
Disc Brakes System Description Servicing Information
| • | Replace all components included in the repair kits. |
| • | Lubricate the parts as specified. |
| • | Do not use lubricated shop air on the brake parts. Shop air can damage the rubber components. |
| • | If necessary, bleed all or part of the brake system after any hydraulic component has been removed or disconnected. |
| • | Replace brake pads in axle sets only. |
| • | The torques specified are for dry, unlubricated fasteners. |
| • | Perform service operations on a clean bench. Verify that the bench is free from mineral oil and other contaminants. |
| • | Use extreme care when doing any work around antilock components in order to prevent damage or misalignment. |
| • | Pump the brake pedal several times in order to make sure it is firm prior to moving the vehicle. Do not move the vehicle until a firm pedal has been obtained. Check the brake fluid level in the master cylinder after pumping the brakes. |
Disc Brakes System Description Caliper Description
The brake caliper has a single piston. Two mounting bolts hold the caliper in place. The caliper is mounted on the steering knuckle. The caliper moves laterally on the steering knuckle when the brakes are applied. The caliper is a one-piece casting with the piston bore(s) on the inboard side. A square-cut rubber seal fits in a groove in each piston bore. The square-cut rubber seal provides a hydraulic seal between the piston and the caliper bore.
Disc Brakes System Description Rotor Description
The front disc brakes use a combination rotor and hub assembly. The rotor and hub are combined on 2WD vehicles. The rotor is separate from the hub on F4WD vehicles.
The rotor turns freely between the linings, until the caliper forces the linings against the rotor. The vented area between the rotor braking surfaces allows for efficient heat dissipation.
