2004 Chevrolet Impala Brake Service (ONLINE REPAIR MANUALS)

Brake fluid is corrosive to painted surfaces. Care must be taken not to allow brake fluid to come in contact with painted surfaces on vehicle.

When bleeding the brake system, always bleed righthand rear wheel circuit first, followed by the lefthand front, lefthand rear and, finally, righthand front.

Manual

Pressure bleeding is recommended for all hydraulic systems. However, if a pressure bleeder is unavailable, use the following procedure. Brake fluid damages painted surfaces. Immediately clean any spilled fluid.

• Remove vacuum reserve by pumping brakes several times with engine o...

Two basic types of power assist mechanisms are used: vacuum assist diaphragm assemblies, which use engine vacuum or, in some cases vacuum pressure developed by an external vacuum pump. The second type is a hydraulic pressure assist mechanism, which use pressure developed by an external pump (usually the power steering pump). Both systems act to increase the force exerted on the master cylinder piston by the operator. This in turn increases the hydraulic pressure delivered to the wheel cylinders while decreasing driver effort required to obtain acceptable stopping performance.

Vac...

AC-Delco Tandem Diaphragm Type

This unit utilizes a vacuum power chamber, consisting of a front and rear shell, housing divider, front and rear diaphragm, plate assemblies, hydraulic pushrod and a diaphragm return spring, Fig. .

In normal operating mode, with service brakes in released position, the booster operates with vacuum on both sides of its diaphragms. When brakes are applied, air at atmospheric pressure is admitted to one side of each diaphragm to provide power assist. When the service brake is released, atmospheric air is shut off f...

All Models Except Century, Grand Prix & Regal

• Raise and support vehicle.
• Mark wheel to axle flange relationship for installation alignment, then remove wheel and tire assembly.
• Remove brake hose from caliper. Plug openings in caliper and brake hose.
• Lift able spring to free end of from lever, then disconnect parking brake cable from lever.
• Remove cable support bracket mounting bolt and washer.
• Remove sleeve bolt and caliper.
• Remove mounting bolts and caliper mounting bracket.
• Remove rotor from hub and bearing.
• Reverse procedure to...

The most common cause of brake chatter on disc brakes is a variation in disc thickness. If roughness or vibration is encountered during highway operation or if pedal pulsation is experienced at low speeds, the disc may have excessive thickness variation. To inspect for this condition, measure the disc at 12 points with a micrometer at a radius appro...