Brakes and Traction Control: Description and Operation

When a vehicle needs to be stopped, the driver applies the brake pedal. The brake pedal pushes the input rod of the power brake booster into the booster. The booster uses vacuum to ease pedal effort as force is transferred through the booster to the master cylinder. The booster's output rod pushes in the master cylinder's primary and secondary pistons applying hydraulic pressure through the chassis brake tubes and proportioning valves to the brakes at each tire and wheel assembly.

Front disc brakes control the braking of the front wheels; rear braking is controlled by rear drum brakes as standard equipment. Rear disc brakes are optional.

The hydraulic brake system is diagonally split on both the non-antilock and antilock braking systems. This means the left front and right rear brakes are on one hydraulic circuit and the right front and left rear are on the other.

Vehicles equipped with the optional Antilock Brake System (ABS) use a system designated Mark 20, which is supplied by ITT Teves. This system shares most base brake hardware used on vehicles without ABS. A vehicle equipped with ABS, however, uses a different power brake booster, master cylinder, and brake tubes. Also included in the ABS system is an Integrated Control Unit (ICU), four wheel speed sensors, and an electronic controller referred to as the Controller Antilock Brake (CAB).

The parking brakes are hand-operated. When applied, the parking brake lever pulls on cables that actuate brake shoes at each rear wheel. The parking brake lever has an automatic adjusting feature that takes up any excessive slack in the parking brake system.