GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 1999 🢒 Alero Export 🢒 Brakes 🢒 Hydraulic Brakes 🢒 Hydraulic Brake System Flushing

Caution: Do not move the vehicle until a firm brake pedal is obtained. Air in the brake system can cause loss of brakes with possible personal injury.

Caution: Use only SUPREME 11 or equivalent DOT 3 brake fluid from a clean, sealed container. Do not use fluid from an open container that may be contaminated with water. Improper or contaminated fluid will result in damage to components or loss of braking, with possible personal injury.

Caution: Do not overfill the brake fluid reservoir. Overfilling the brake fluid reservoir may cause the brake fluid to overflow onto the engine exhaust components during brake system service. The brake fluid is flammable and may cause a fire and personal injury if the brake fluid contacts the engine exhaust system components.

Notice: If any brake component is repaired or replaced such that air is allowed to enter the brake system, the entire bleeding procedure must be followed.

Notice: Avoid spilling brake fluid on any of the vehicle's painted surfaces, wiring, cables, or electric connectors. Brake fluid will damage the paint and the electrical connections. If any fluid is spilled on the vehicle, flush the area to lessen the damage.

Notice: Prior to bleeding the brakes, the front and rear displacement cylinder pistons must be returned to the topmost position. The preferred method uses a Scan Tool to perform the rehoming procedure. If a Scan Tool is not available, the second procedure may be used, but it is extremely important that the procedure be followed exactly as outlined.

A bleeding operation is necessary in order to remove air when air is introduced into the hydraulic brake system.

Bleed the hydraulic system at all four brakes if air has been introduced through a low fluid level or by disconnecting brake pipes at the master cylinder. If a brake hose or brake pipe is disconnected at one wheel, bleed only that one wheel caliper. If brake pipes or hoses are disconnected at any fitting located between the master cylinder and the brakes, then only bleed the brake system served by the disconnected pipe or hose.

Pressure Flushing

Tools Required

    • J 29532 Diaphragm Type Brake Bleeder
    • J 35589 Compact Brake Bleeder Adapter

    Important: 

       • If evidence of contamination is present in the vehicle's brake fluid, flush the entire brake system following one of the following procedures.
       • Flush the system under the following conditions:
          - If there is any doubt about the condition of the fluid in the system
          - If the fluid that is used contains the slightest trace of mineral oil (engine oil, transmission fluid, etc.)
       • After flushing the entire brake system, replace all rubber components.
       • Replace the following components. Refer to the appropriate replacement procedures.
          - The brake hose assemblies
          - The master cylinder rubber parts
          - The brake caliper and wheel cylinder boots and seals
          - The ABS modulator
          - The proportioning valve
       • After replacing all rubber components, re-flush the entire brake system by performing one of the following procedures.
       • After performing the second flushing procedure, perform a complete system bleed. Refer to Hydraulic Brake System Bleeding .


    Object Number: 389030 Size: SH

    Notice: Pressure Bleeding equipment can be used to perform the flush procedure. The pressure bleeding equipment used for flushing must be of the diaphragm type. It must a have a rubber diaphragm between the air supply and the brake fluid to prevent air, moisture, and other contaminants from entering the hydraulic system.

  1. Remove the battery. Refer to Battery Replacement in Engine Electrical.
  2. Remove the battery tray.
  3. Clean the brake fluid reservoir cover and the surrounding area.
  4. Remove the brake fluid reservoir cover.
  5. Remove any remaining brake fluid in the reservoir.

    6. Object Number: 385195 Size: SH
  6. Refill the brake fluid reservoir with clean DOT 3 brake fluid to the proper level (1).

    7. Object Number: 389030 Size: SH
  7. Connect the J 35589 to the brake fluid reservoir.
  8. Install the J 35589 to the pressure bleeding equipment.
  9. Adjust the pressure bleed equipment to 242 kPa (35 psi).
  10. Complete the following procedures using pressure bleeding equipment that is connected and pressurized:

    11. Object Number: 165923 Size: MH
    10.1. Attach a clear plastic bleeder hose to the rearward bleeder valve on the brake modulator.
    10.2. Submerge the opposite hose end in a clean container partially filled with clean brake fluid.
    10.3. Slowly open the bleeder valve. Allow the brake fluid to flow clean or until at least 118 ml (4 oz) of fluid accumulates.
    10.4. Close the valve.

    Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

    10.5. Repeat the above procedure for the forward bleeder valve until clean brake fluid flows or until at least 118 ml (4 oz) of fluid accumulates.

    Tighten
    Tighten the ABS brake modulator bleeder valves to 9 N·m (80 lb in).

  11. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.

    12. Object Number: 179295 Size: SH
  12. Use the following bleed sequence to bleed the system.
    13. • Right rear
    • Left front
    • Left rear
    • Right front
  13. Bleed the wheel brakes in the sequence shown above:

    14. Important: Ensure that the bleeder valves do not leak.

  14. Complete the following steps in order to bleed the brakes:
    15. 13.1. Attach a clear plastic bleeder hose (3) to the bleeder valve at the wheel.
    13.2. Submerge the opposite hose end in a clean container (2) partially filled with clean brake fluid.
    13.3. Slowly open the bleeder valve and allow the fluid to flow.
    13.4. Close the valve when clean brake fluid begins to flow or at least 235 ml (8 oz) of fluid accumulates.

    Tighten

        • Tighten the front caliper bleeder valves to 13 N·m (115 lb in).
        • Tighten rear caliper bleeder valves to 7 N·m (62 lb in).
        • Tighten the rear wheel cylinder bleeder valves to 7 N·m (62 lb in).
  15. Lower the vehicle.
  16. Remove the pressure bleeding equipment, including the J 35589 .
  17. Replace all the rubber components listed under the flushing procedure. Refer to the appropriate On-Vehicle Service section.
  18. Repeat the flushing procedure.

    19. Object Number: 385195 Size: SH
  19. Inspect the brake fluid level in the reservoir (1). Fill the reservoir to the correct level if necessary.
  20. Install the brake fluid reservoir cap.
  21. Bleed the entire brake hydraulic system. Refer to Hydraulic Brake System Bleeding .
  22. Install the battery tray.
  23. Install the battery. Refer to Battery Replacement in Engine Electrical.

Manual Flushing

Important: Use a suitable container and/or shop rags in order to catch fluid and prevent the fluid from contacting any painted surfaces.

  1. Remove the battery. Refer to Battery Replacement in Engine Electrical.
  2. Remove the battery tray.

    3. Object Number: 385195 Size: SH
  3. Clean the brake fluid reservoir cover and the surrounding area.
  4. Remove the brake fluid reservoir cover.
  5. Remove any remaining brake fluid in the brake fluid reservoir.
  6. Refill the brake fluid reservoir with clean DOT 3 brake fluid to the proper level (1).
  7. Install the brake fluid reservoir cover.

    8. Object Number: 165923 Size: MH
  8. Use the following procedure in order to flush the brake modulator:
    9. 8.1. Attach the bleeder hose to the rearward bleeder valve.
    8.2. Submerge the opposite hose end in a clean container partially filled with clean brake fluid.
    8.3. Slowly open the rearward bleeder valve.
    8.4. Depress the brake pedal and hold the pedal until the fluid begins to flow.
    8.5. Close the valve and release the brake pedal. Repeat the above steps until clean brake fluid flows or at least 118 ml (4 oz) of fluid accumulates.

    Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

    8.6. Repeat the procedure for the forward bleeder valve until clean brake fluid flows or at least 118 ml (4 oz) of fluid accumulates.

    Tighten
    Tighten the ABS brake modulator bleeder valves to 9 N·m (80 lb in).

  9. Inspect the brake fluid level in the following manner:
    10. 9.1. Remove the brake fluid reservoir cover.

    Object Number: 385195 Size: SH
    9.2. Inspect the brake fluid level in the reservoir. Fill the reservoir to the correct level if necessary.
    9.3. Replace the brake fluid reservoir cover (1).
  10. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.

    11. Object Number: 179295 Size: SH
  11. Use the following bleed sequence in order to flush the system.
    12. • Right rear
    • Left front
    • Left rear
    • Right front
  12. Bleed the wheel brakes in the sequence shown above:

    13. Important: Ensure that the bleeder valves do not leak.

  13. Complete the following steps in order to bleed the brakes:
    14. 12.1. Attach a clear plastic bleeder hose (3) to the bleeder valve at the wheel.
    12.2. Submerge the opposite hose end in a clean container (2) partially filled with clean brake fluid.
    12.3. Slowly open the bleeder valve and allow the fluid to flow.
    12.4. Close the valve when clean brake fluid begins to flow or at least 235 ml (8 oz) of fluid accumulates.

    Tighten

        • Tighten the front caliper bleeder valves to 13 N·m (115 lb in).
        • Tighten rear caliper bleeder valves to 7 N·m (62 lb in).
        • Tighten the rear wheel cylinder bleeder valves to 7 N·m (62 lb in).
  14. Lower the vehicle.

    15. Object Number: 385195 Size: SH
  15. Remove the brake fluid reservoir cover.
  16. Inspect the brake fluid level in the reservoir (1). Fill the reservoir to the correct level if necessary.
  17. Install the brake fluid reservoir cover.
  18. Replace all of the following rubber components:
    19. • The brake hose assemblies
    • The master cylinder rubber parts
    • The brake caliper and wheel cylinder boots and seals
    • The ABS modulator
    • The proportioning valve
  19. Repeat the manual flushing procedure.
  20. Inspect the brake fluid level in the reservoir. Fill the reservoir to the correct level if necessary.
  21. Replace the brake fluid reservoir cap.
  22. Bleed the entire brake hydraulic system. Refer to Hydraulic Brake System Bleeding .
  23. Install the battery tray.
  24. Install the battery. Refer to Battery Replacement in Engine Electrical.