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Disc Brakes (Rear)

DESCRIPTION






This vehicle has rear disc brakes as standard equipment.
The rear disc brake system used on this vehicle is similar to the front disc brake system. The rear disc brake system contains the following components:
^ Disc brake caliper
^ Brake shoes
^ Caliper adapter
^ Brake rotor

The single-piston, double-pin floating disc brake caliper is a one piece structure made of cast iron. The inboard side of the caliper has a single bore containing a 54 mm (2.13 inch) phenolic piston. The brake caliper is mounted to the caliper adapter using guide pin bolts.
The brake shoe lining material is an organic nonasbestos formula. The brake lining material used has been specifically formulated to be compatible with the special rotors used on the rear brakes, and to meet the braking requirements of the vehicle. When brake shoes are replaced, only brake shoes meeting the original equipment manufacturer formulation (such as Mopar (R) replacement parts) should be used. This will maintain the original braking performance of the vehicle and will not cause damage to the rotors.
The caliper adapter is mounted to the rear knuckle between the knuckle and the hub and bearing. The caliper adapter mounts the rear disc brake caliper to the knuckle and is used to mount the parking brake shoes and actuating cables to the vehicle. The caliper adapter has two machined abutments which are used to position and align the caliper and brake shoes for inboard and outboard movement of the caliper.







The brake rotor is made of aluminum silica carbide alloy and is vented to help cool it during brake applications. The brake rotor has two slits cut into the harking surface.
The brake rotor has a drum formed into its inside area for the parking brake system. This type of rotor is known as a drum-in-hat style brake rotor.

OPERATION
Rear disc brakes operate similarly to front disc brakes.
The two machined abutments on the caliper adapter position and align the caliper fore-and-aft. The guide pin bolts, sleeves, and bushings control the side-to-side movement of the caliper.
The single-piston, double-pin floating disc brake caliper operates in the following manner. As hydraulic pressure is applied to the rear of the piston in the caliper, the piston moves outward applying the inboard brake shoe. At the same time the inboard shoe begins to apply against the brake rotor, the force causes the caliper to move inward, sliding on the guide pin bolts and sleeves. This action applies the outboard brake shoe. When hydraulic pressure is released, the caliper returns to its original position.







The square cut rubber piston seal provides a hydraulic seal between the piston and the cylinder wall. The piston seal is designed to pull the piston back into the cylinder bore in the caliper when the brakes are released. This action also helps maintain proper brake shoe-to-rotor clearance.
The molded rubber dust boot prevents contamination of the piston and the bore area of the brake caliper.
The brake rotor slows down and stops the rear wheels of the vehicle. This is accomplished by applying the brake shoes against the braking surfaces of the rotor.
The two slits cut into the braking surface of the rear brake rotor are there to isolate brake noise.
The brake rotor serves a dual purpose. Its secondary role is to use the inside of the rotor as a parking brake drum. When the parking brake is applied, the parking brake shoes expand out against a braking surface (drum-in-hat section) on the inside area of the rear brake rotor.