GM Service Manual Online
For 1990-2009 cars only

Hydraulic Brake System Flushing ABS w/o Traction Control

Notice: Use only DOT 3 brake fluid from a clean, sealed container. Do not use any fluid from a container which is wet with water. Do not use DOT 5 silicone brake fluid. Improper brake fluid, mineral oil or water in the fluid may cause the brake fluid to boil or the rubber components to deteriorate. Keep all fluid containers capped to prevent contamination.

Important: 

   • If evidence of contamination is present in the vehicle's brake fluid, flush the entire brake system. Use one of the following procedures below.
   • After flushing the entire brake system, replace all rubber components.
   • Replace the following components:
      - Brake hoses
      - Master cylinder rubber parts
      - Brake caliper and wheel cylinder boots and seals
      - Combination valve
      - ABS hydraulic modulator
   • Refer to the appropriate replacement procedures.
   • 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
   • Flush the system if there is any doubt about the condition of the fluid in the system or if the fluid used contains the slightest trace of mineral oil (from such things as engine oil, transmission fluid, etc.)

Flushing Preparation

Notice: The flushing prep procedure must be performed prior to using "Pressure Flush" or "Manual Flush" procedures.

Important: Do not place your foot on the brake pedal through this entire procedure unless specifically directed to do so.

  1. Remove your foot from the brake pedal.
  2. Start the engine.
  3. Allow the engine to run for at least 10 seconds. Observe the amber ABS warning lamp.
  4. If the amber ABS warning lamps turn ON and stay ON after 10 seconds, stop the flushing procedure.
  5. If the amber ABS warning lamps turn ON for approximately 3 seconds, then turn OFF and stay OFF, turn the ignition OFF.
  6. Repeat the previous five steps one more time.
  7. Flush the entire brake system. Use the Pressure Flush procedure or the Manual Flush procedure.

Pressure Flush

Tools Required

J 35589 Bleeding Adapter

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. Clean the fluid reservoir cover and the surrounding area.
  2. Remove the fluid reservoir cover.
  3. Remove any remaining brake fluid in the reservoir.
  4. Refill the reservoir with clean DOT 3 brake fluid to the proper level.
  5. Install the J 35589 to the brake fluid reservoir.
  6. Install the J 35589 to the pressure bleeding equipment.
  7. Adjust the pressure bleeding equipment to 35-70 kPa (5-10 psi). Wait for approximately 30 seconds in order to ensure that there is no leakage.
  8. Adjust the pressure bleeding equipment to 205-240 kPa (30-35 psi).
  9. After connecting the pressure bleeding equipment and pressurizing the system, perform the following steps:
  10. 9.1. Attach a clear plastic hose to the rearward bleeder valve on the ABS hydraulic modulator.

    Place the other end of the hose in a container in order to collect the draining brake fluid. Do not submerge the hose end into the fluid.

    9.2. Slowly open the bleeder valve. Allow the fluid to flow until clean brake fluid flows or until at least 118 ml (4 oz) of fluid accumulates.
    9.3. Close the valve.
    9.4. Repeat the previous three steps for the forward bleeder valve until clean brake fluid flows or until 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.

    Tighten
    The ABS hydraulic modulator bleeder valve to 9 N·m (80 lb in).

  11. Raiseand suitably support the vehicle. Refer to Lifting and Jacking the Vehicle
  12. Important: Flush sequence: Right rear, left front, right front, left rear.

  13. Flush the wheel brakes in the sequence shown above. Use the following procedure:
  14. 11.1. Attach the bleeder hose to the bleeder valve at each wheel.

    Place the other end into a container in order to collect the draining brake fluid. Do not submerge the hose end into the fluid.

    11.2. Slowly open the bleeder valve. Allow the fluid to flow.
    11.3. Close the valve when clean brake fluid begins to flow or at least 235 ml (8 oz) of fluid accumulates.
  15. Lower the vehicle.
  16. Remove the bleeder adapter.
  17. Replace all the rubber components listed in Flushing Procedure in this section.
  18. Repeat the flushing preparation and the flushing procedure one more time.
  19. Inspect the brake fluid level in the reservoir. 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 .

Manual Flush

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

  1. Clean the fluid reservoir cover and the surrounding area.
  2. Remove the fluid reservoir cover.
  3. Remove any remaining brake fluid in the reservoir.
  4. Refill the reservoir with clean DOT 3 brake fluid to the proper level.
  5. Install the brake fluid reservoir cover.
  6. Use the following procedure in order to flush the ABS hydraulic modulator:
  7. 6.1. Attach a clear plastic bleeder hose to the rearward bleeder valve on the ABS hydraulic modulator.

    Place the other end of the hose in a container in order to collect the draining brake fluid. Do not submerge the hose end into the fluid.

    6.2. Slowly open the rearward bleeder valve one half to one full turn.
    6.3. Depress the brake pedal until the fluid begins to flow.
    6.4. Close the valve. Release the brake pedal. Repeat the previous two 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.

    6.5. Repeat the previous four steps 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).

  8. Remove the fluid reservoir cover.
  9. Inspect the brake fluid level in the reservoir. Fill the reservoir to the correct level if necessary.
  10. Replace the brake fluid reservoir cover.
  11. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle
  12. Important: Flush sequence: Right rear, left front, right front, left rear.

  13. Flush the wheel brakes in the above sequence. Use the following procedure:
  14. 11.1. Attach the bleeder hose to the bleeder valve at each wheel.

    Place the other end into a container in order to collect the draining brake fluid. Do not submerge the hose end in the fluid.

    11.2. Open the bleeder valve.
    11.3. Slowly depress the brake pedal.
    11.4. Close the valve. Slowly release the brake pedal.
    11.5. Repeat the previous three steps until clean brake fluid flows or at least 235 ml (8 oz) of fluid accumulates.
  15. Lower the vehicle.
  16. Replace all the rubber components listed under Flushing Procedure in this section.
  17. Repeat the flushing preparation and the flushing procedure one more time.
  18. Inspect the brake fluid level in the reservoir. Fill the reservoir to the correct level if necessary.
  19. Replace the brake fluid reservoir cap.
  20. Bleed the entire brake hydraulic system. Refer to Hydraulic Brake System Bleeding

Hydraulic Brake System Flushing ABS w/Traction Control

Notice: Use only DOT 3 brake fluid from a clean, sealed container. Do not use any fluid from a container which is wet with water. Do not use DOT 5 silicone brake fluid. Improper brake fluid, mineral oil or water in the fluid may cause the brake fluid to boil or the rubber components to deteriorate. Keep all fluid containers capped to prevent contamination.

Important: 

   • If evidence of contamination is present in the vehicle's brake fluid, flush the entire brake system. Use one of the following procedures:
   • After flushing the entire brake system, replace all rubber components.
   • Replace the following components:
      - Brake hoses
      - Master cylinder rubber parts
      - Brake caliper and wheel cylinder boots and seals
      - Combination valve
      - ABS hydraulic modulator
      - TCS hydraulic modulator
      - ABS solenoids
   • Refer to the appropriate replacement procedures.
   • 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
   • Flush the system if there is any doubt about the condition of the fluid in the system or if the fluid used contains the slightest trace of mineral oil (from such things as engine oil, transmission fluid, etc.)

Flushing Preparation

Notice: The flushing prep procedure must be performed prior to using "Pressure Flush" or "Manual Flush" procedures.

Important: Do not place your foot on the brake pedal through this entire procedure unless specifically directed to do so.

  1. Remove your foot from the brake pedal.
  2. Start the engine.
  3. Allow the engine to run for at least 10 seconds. Observe the amber ABS and TCS warning lamp.
  4. If the ABS or TCS warning lamps turn ON and stay ON after 10 seconds, stop the flushing procedure.
  5. If the ABS or TCS warning lamps turn ON for approximately 3 seconds, then turn OFF and stay OFF, turn the ignition OFF.
  6. Repeat the previous five steps one more time.
  7. Flush the entire brake system. Use the Pressure Flush procedure or the Manual Flush procedure.

Pressure Flush

Tools Required

J 35589 Bleeding Adapter

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. Clean the fluid reservoir cover and the surrounding area.
  2. Remove the fluid reservoir cover.
  3. Remove any remaining brake fluid in the reservoir.
  4. Refill the reservoir with clean DOT 3 brake fluid to the proper level.
  5. Install the J 35589 to the brake fluid reservoir.
  6. Install the J 35589 to the pressure bleeding equipment.
  7. Adjust the pressure bleeding equipment to 35-70 kPa (5-10 psi). Wait for approximately 30 seconds in order to ensure that there is no leakage.
  8. Adjust the pressure bleeding equipment to 205-240 kPa (30-35 psi).
  9. After connecting the pressure bleeding equipment and pressurizing the system, perform the following steps:
  10. 9.1. Attach a clear plastic hose to the rearward bleeder valve on the ABS hydraulic modulator.

    Place the other end of the hose in a container in order to collect the draining brake fluid. Do not submerge the hose end into the fluid.

    9.2. Slowly open the bleeder valve. Allow the fluid to flow until clean brake fluid flows or until at least 118 ml (4 oz) of fluid accumulates.
    9.3. 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.

    9.4. Repeat the previous three steps for the forward bleeder valve until clean brake fluid flows or until at least 118 ml (4 oz) of fluid accumulates.

    Tighten
    The ABS hydraulic modulator bleeder valve to 9 N·m (80 lb in).

  11. Raise the vehicle. Support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  12. Important: Flush sequence: Right rear, left front, right front, left rear.

  13. Flush the wheel brakes in the sequence shown above. Use the following procedure:
  14. 11.1. Attach the bleeder hose to the bleeder valve at each wheel.

    Place the other hose end into a container in order to collect the draining brake fluid. Do not submerge the hose end into the fluid.

    11.2. Slowly open the bleeder valve. Allow the fluid to flow.
    11.3. Close the valve when clean brake fluid begins to flow or at least 235 ml (8 oz) of fluid accumulates.
  15. Lower the vehicle.
  16. Remove the J 35589 .
  17. Replace all the rubber components listed in Flushing Procedure in this section.
  18. Repeat the flushing preparation and the flushing procedure one more time.
  19. Inspect the brake fluid level in the reservoir. 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

Manual Flush

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

  1. Clean the fluid reservoir cover and the surrounding area.
  2. Remove the fluid reservoir cover.
  3. Remove any remaining brake fluid in the reservoir.
  4. Refill the reservoir with clean DOT 3 brake fluid to the proper level.
  5. Install the brake fluid reservoir cover.
  6. Flush the ABS hydraulic modulator. Use the following procedure:
  7. 6.1. Attach a clear plastic bleeder hose to the rearward bleeder valve on the ABS hydraulic modulator.

    Place the other end of the hose in a container in order to collect the draining brake fluid. Do not submerge the hose end into the fluid.

    6.2. Slowly open the rearward bleeder valve one half to one full turn.
    6.3. Depress the brake pedal until the fluid begins to flow.
    6.4. Close the valve. Release the brake pedal.
    6.5. Repeat the previous three steps until clean brake fluid flows or at least 118 ml (4 oz) of fluid accumulates.
    6.6. Repeat the previous five steps 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).

  8. Remove the fluid reservoir cover.
  9. Inspect the brake fluid level in the reservoir. Fill the reservoir to the correct level if necessary.
  10. Replace the brake fluid reservoir cover.
  11. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle
  12. Important: Wheel position flush sequence: Right rear, left front, right front, left rear.

  13. Flush the wheel brakes in the sequence shown above. Use the following procedure:
  14. 11.1. Attach the bleeder hose to the bleeder valve at each wheel.

    Place the other end into a container in order to collect the draining brake fluid. Do not submerge the hose end in fluid.

    11.2. Open the bleeder valve.
    11.3. Slowly depress the brake pedal.
    11.4. Close the valve. Slowly release the brake pedal.
    11.5. Repeat the previous three steps until clean brake fluid flows or at least 235 ml (8 oz) of fluid accumulates.
  15. Lower the vehicle.
  16. Replace all the rubber components listed under Flushing Procedure in this section.
  17. Repeat the flushing preparation and the flushing procedure one more time.
  18. Inspect the brake fluid level in the reservoir. Fill the reservoir to the correct level if necessary.
  19. Replace the brake fluid reservoir cap.
  20. Bleed the entire brake hydraulic system. Refer to Hydraulic Brake System Bleeding