GM Service Manual Online
For 1990-2009 cars only

Hydraulic Brake System Bleeding Manual

Caution: Refer to Brake Fluid Irritant Caution in the Preface section.

Caution: Do not remove the reservoir cap while depressing and releasing the brake pedal. If the cap is removed while depressing and releasing the brake pedal, pressurized brake fluid being returned to the reservoir may leave the reservoir. Personal injury or vehicle damage could result.

Notice: Refer to Brake Fluid Effects on Paint and Electrical Components Notice in the Preface section.

Notice: When adding fluid to the brake master cylinder reservoir, use only Delco Supreme 11®, GM P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake fluid container. The use of any type of fluid other than the recommended type of brake fluid, may cause contamination which could result in damage to the internal rubber seals and/or rubber linings of hydraulic brake system components.

Notice: Do Not allow the HBCi pump and motor to run more than 1 minute continuously. Allow 2 minutes cool down time between pump run times. Extended pump and motor run time could create excessive heat, and damage the pump and motor assembly.

  1. Place a clean shop cloth beneath the brake master cylinder to prevent brake fluid spills.
  2. If you disconnected the brake pipes from the master cylinder, you must perform the following steps:
  3. 2.1. Ensure that the brake master cylinder reservoir is full to the maximum-fill level. If necessary add Delco Supreme 11®, GM P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake fluid container.

    If removal of the reservoir cap and diaphragm is necessary, clean the outside of the reservoir on and around the cap prior to removal.


    Object Number: 1633122  Size: SH
    2.2. With all brake pipes installed securely to the master cylinder, loosen and separate the left front brake pipe (4) from the left front port of the brake master cylinder.
    2.3. Allow a small amount of brake fluid to gravity bleed from the open port of the master cylinder.
    2.4. Reconnect the brake pipe to the master cylinder port and tighten securely.
    2.5. Have an assistant slowly depress the brake pedal fully and maintain steady pressure on the pedal.
    2.6. Loosen the same brake pipe to purge air from the open port of the master cylinder.
    2.7. Tighten the brake pipe, then have the assistant slowly release the brake pedal.
    2.8. Wait 15 seconds, then repeat steps 2.5-2.7 until all air is purged from the same port of the master cylinder.
    2.9. With the left front brake pipe (4) installed securely to the master cylinder, after all air has been purged from the left front port of the master cylinder, loosen and separate the right front brake pipe (3) from the master cylinder, then repeat steps 2.5-2.8.
    2.10. Turn the ignition key to the ON position.
    2.11. With the right front brake pipe (3) installed securely to the master cylinder, after all air has been purged from the right front port of the master cylinder, loosen and separate the left rear brake pipe (1) from the master cylinder, then repeat steps 2.5-2.8.
    2.12. With the left rear brake pipe (1) installed securely to the master cylinder, after all air has been purged from the left rear port of the master cylinder, loosen and separate the right rear brake pipe (2) from the master cylinder, then repeat steps 2.5-2.8.
    2.13. After completing the final master cylinder port bleeding procedure, ensure that all of the brake pipe-to-master cylinder fittings are properly tightened.
    2.14. Turn the ignition key to the OFF position. Depress the brake pedal 20 times.
  4. Fill the brake master cylinder reservoir with Delco Supreme 11®, GM P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake fluid container. Ensure that the brake master cylinder reservoir remains at least half-full during this bleeding procedure. Add fluid as needed to maintain the proper level.
  5. Clean the outside of the reservoir on and around the reservoir cap prior to removing the cap and diaphragm.

  6. Install a proper box-end wrench onto the RIGHT REAR wheel hydraulic circuit bleeder valve.
  7. Install a transparent hose over the end of the bleeder valve.
  8. Submerge the open end of the transparent hose into a transparent container partially filled with Delco Supreme 11®, GM P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake fluid container.
  9. Have an assistant turn the ignition ON, then partially apply and hold the brake pedal. DO NOT pump the brake pedal. Fluid will flow when the bleed valves are opened.
  10. Loosen the bleeder valve to purge air from the wheel hydraulic circuit.
  11. Tighten the bleeder valve, then have the assistant slowly release the brake pedal.
  12. Wait 15 seconds, then repeat steps 7-9 until all air is purged from the same wheel hydraulic circuit.
  13. With the right rear wheel hydraulic circuit bleeder valve tightened securely, after all air has been purged from the right rear hydraulic circuit, install a proper box-end wrench onto the LEFT REAR wheel hydraulic circuit bleeder valve.
  14. Install a transparent hose over the end of the bleeder valve, then repeat steps 6-10.
  15. Turn the ignition OFF. The assistant will now have to pump the brake pedal for fluid to flow from open bleed valves.
  16. With the left rear wheel hydraulic circuit bleeder valve tightened securely, after all air has been purged from the left rear hydraulic circuit, install a proper box-end wrench onto the RIGHT FRONT wheel hydraulic circuit bleeder valve.
  17. Install a transparent hose over the end of the bleeder valve, then repeat steps 7-11.
  18. With the right front wheel hydraulic circuit bleeder valve tightened securely, after all air has been purged from the right front hydraulic circuit, install a proper box-end wrench onto the LEFT FRONT wheel hydraulic circuit bleeder valve.
  19. Install a transparent hose over the end of the bleeder valve, then repeat steps 7-11.
  20. After completing the final wheel hydraulic circuit bleeding procedure, ensure that each of the 4 wheel hydraulic circuit bleeder valves are properly tightened.
  21. Fill the brake master cylinder reservoir to the maximum-fill level with Delco Supreme 11®, GM P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake fluid container. Refer to Master Cylinder Reservoir Filling .
  22. Slowly depress and release the brake pedal. Observe the feel of the brake pedal.
  23. If the brake pedal feels spongy, repeat the bleeding procedure again. If the brake pedal still feels spongy after repeating the bleeding procedure, perform the following steps:
  24. 21.1. Inspect the brake system for external leaks. Refer to Brake System External Leak Inspection .
    21.2. Pressure bleed the hydraulic brake system in order to purge any air that may still be trapped in the system.
  25. Turn the ignition key ON, with the engine OFF. Check to see if the brake system warning lamp remains illuminated.
  26. Important: If the brake system warning lamp remains illuminated, DO NOT allow the vehicle to be driven until it is diagnosed and repaired.

  27. If the brake system warning lamp remains illuminated, refer to Symptoms - Hydraulic Brakes .

Hydraulic Brake System Bleeding Pressure

Tools Required

    • J 29532 Diaphragm Pressure Bleeder, or equivalent
    • J 35589-A Master Cylinder Bleeder Adapter
    • J 44894-A Brake Bleeder Adapter

Caution: Refer to Brake Fluid Irritant Caution in the Preface section.

Caution: Do not remove the reservoir cap while depressing and releasing the brake pedal. If the cap is removed while depressing and releasing the brake pedal, pressurized brake fluid being returned to the reservoir may leave the reservoir. Personal injury or vehicle damage could result.

Notice: Refer to Brake Fluid Effects on Paint and Electrical Components Notice in the Preface section.

Notice: When adding fluid to the brake master cylinder reservoir, use only Delco Supreme 11®, GM P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake fluid container. The use of any type of fluid other than the recommended type of brake fluid, may cause contamination which could result in damage to the internal rubber seals and/or rubber linings of hydraulic brake system components.

Notice: Do Not allow the HBCi pump and motor to run more than 1 minute continuously. Allow 2 minutes cool down time between pump run times. Extended pump and motor run time could create excessive heat, and damage the pump and motor assembly.

  1. Place a clean shop cloth beneath the brake master cylinder to prevent brake fluid spills.
  2. If you disconnected the brake pipes from the master cylinder, you must perform the following steps:
  3. 2.1. Ensure that the brake master cylinder reservoir is full to the maximum-fill level. If necessary add Delco Supreme 11®, GM P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake fluid container.

    If removal of the reservoir cap and diaphragm is necessary, clean the outside of the reservoir on and around the cap prior to removal.


    Object Number: 1633122  Size: SH
    2.2. With all the brake pipes installed securely to the master cylinder, loosen and separate the left front brake pipe (4) from the left front port of the brake master cylinder.
    2.3. Allow a small amount of brake fluid to gravity bleed from the open port of the master cylinder.
    2.4. Reconnect the brake pipe to the master cylinder port and tighten securely.
    2.5. Have an assistant slowly depress the brake pedal fully and maintain steady pressure on the pedal.
    2.6. Loosen the same brake pipe to purge air from the open port of the master cylinder.
    2.7. Tighten the brake pipe, then have the assistant slowly release the brake pedal.
    2.8. Wait 15 seconds, then repeat steps 2.5-2.7 until all air is purged from the same port of the master cylinder.
    2.9. With the left front brake pipe (4) installed securely to the master cylinder, after all air has been purged from the left front port of the master cylinder, loosen and separate the right front brake pipe (3) from the master cylinder, then repeat steps 2.5-2.8.
    2.10. Turn the ignition key to the ON position.
    2.11. With the right front brake pipe (3) installed securely to the master cylinder, after all air has been purged from the right front port of the master cylinder, loosen and separate the right rear brake pipe (2) from the master cylinder, then repeat steps 2.5-2.8.
    2.12. With the right rear brake pipe (2) installed securely to the master cylinder, after all air has been purged from the right rear port of the master cylinder, loosen and separate the left rear brake pipe (1) from the master cylinder, then repeat steps 2.5-2.8.
    2.13. After completing the final master cylinder port bleeding procedure, ensure that all of the brake pipe-to-master cylinder fittings are properly tightened.
    2.14. Turn the ignition key to the OFF position. Depress the brake pedal 20 times.
  4. Fill the brake master cylinder reservoir to the maximum-fill level with Delco Supreme 11®, GM P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake fluid container.
  5. Clean the outside of the reservoir on and around the reservoir cap prior to removing the cap and diaphragm.

  6. Install the J 44894-A to the brake master cylinder reservoir.
  7. Check the brake fluid level in the J 29532 , or equivalent. Add Delco Supreme 11®, GM P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake fluid container as necessary to bring the level to approximately the half-full point.
  8. Connect the J 29532 , or equivalent, to the J 44894-A .
  9. Charge the J 29532 , or equivalent, air tank to 175-205 kPa (25-30 psi).
  10. Open the J 29532 , or equivalent, fluid tank valve to allow pressurized brake fluid to enter the brake system.
  11. Wait approximately 30 seconds, then inspect the entire hydraulic brake system in order to ensure that there are no existing external brake fluid leaks.
  12. Any brake fluid leaks identified require repair prior to completing this procedure.

  13. Install a proper box-end wrench onto the RIGHT REAR wheel hydraulic circuit bleeder valve.
  14. Install a transparent hose over the end of the bleeder valve.
  15. Submerge the open end of the transparent hose into a transparent container partially filled with Delco Supreme 11®, GM P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake fluid container.
  16. Loosen the bleeder valve to purge air from the wheel hydraulic circuit. Allow fluid to flow until air bubbles stop flowing from the bleeder, then tighten the bleeder valve.
  17. With the right rear wheel hydraulic circuit bleeder valve tightened securely, after all air has been purged from the right rear hydraulic circuit, install a proper box-end wrench onto the LEFT REAR wheel hydraulic circuit bleeder valve.
  18. Install a transparent hose over the end of the bleeder valve, then repeat steps 13-14.
  19. With the left rear wheel hydraulic circuit bleeder valve tightened securely, after all air has been purged from the left rear hydraulic circuit, install a proper box-end wrench onto the RIGHT FRONT wheel hydraulic circuit bleeder valve.
  20. Install a transparent hose over the end of the bleeder valve, then repeat steps 13-14.
  21. With the right front wheel hydraulic circuit bleeder valve tightened securely, after all air has been purged from the right front hydraulic circuit, install a proper box-end wrench onto the LEFT FRONT wheel hydraulic circuit bleeder valve.
  22. Install a transparent hose over the end of the bleeder valve, then repeat steps 13-14.
  23. After completing the final wheel hydraulic circuit bleeding procedure, ensure that each of the 4 wheel hydraulic circuit bleeder valves are properly tightened.
  24. Close the J 29532 , or equivalent, fluid tank valve, then disconnect the J 29532 , or equivalent, from the J 44894-A .
  25. Remove the J 44894-A from the brake master cylinder reservoir.
  26. Fill the brake master cylinder reservoir. Refer to Master Cylinder Reservoir Filling .
  27. Slowly depress and release the brake pedal. Observe the feel of the brake pedal.
  28. If the brake pedal feels spongy perform the following steps:
  29. 25.1. Inspect the brake system for external leaks. Refer to Brake System External Leak Inspection .
    25.2. Using a scan tool, perform the antilock brake system automated bleeding procedure to remove any air that may have been trapped in the HBCi. Refer to Antilock Brake System Automated Bleed Procedure .
  30. Turn the ignition key ON, with the engine OFF. Check to see if the brake system warning lamp remains illuminated.
  31. Important: If the brake system warning lamp remains illuminated, DO NOT allow the vehicle to be driven until it is diagnosed and repaired.

  32. If the brake system warning lamp remains illuminated, refer to Symptoms - Hydraulic Brakes .