GM Service Manual Online
For 1990-2009 cars only

Bleed Procedure

Tools Required

    • J 35555 Mighty Vac
    • J 43485 Power Steering Bleeder Adapter

Important: Use clean, new power steering fluid only.

    • Bleed the power steering system for the following reasons:
       - Components replaced
       - Fluid line disconnected
       - Steering system noise occurs
       - Prevention of pump damage
       - Proper system operation

       Important: Hoses touching the frame, body or engine can cause system noise.

    • The hoses must not touch any other part of the vehicle.

    Important: Loose connections may not leak, but could allow air into the steering system.

  1. Verify that all hose connections are tight.

  2. Object Number: 468993  Size: SH

    Important: Maintain the power steering fluid level throughout the bleed procedure.

  3. Remove the power steering pump reservoir cap.
  4. Fill the power steering pump reservoir with power steering fluid to the "FULL COLD" level.

  5. Object Number: 443650  Size: SH
  6. Reinstall the power steering pump reservoir cap.
  7. Start the engine. Allow the engine to idle.
  8. Turn off the engine.
  9. Verify the power steering fluid level. Repeat steps 8 through 10 until the power steering fluid stabilizes.

  10. Object Number: 443653  Size: SH
  11. Start the engine. Allow the engine to idle.
  12. Important: Do not turn steering wheel to lock.

  13. Turn the steering wheel 180-360 degrees in both directions 5 times.

  14. Object Number: 443655  Size: SH
  15. Switch the ignition off.

  16. Object Number: 468993  Size: SH
  17. Remove the power steering pump reservoir cap and verify the power steering fluid level.

  18. Object Number: 468993  Size: SH
  19. Reinstall the power steering pump reservoir cap.

Special Conditions Procedure


    Object Number: 443667  Size: SH
  1. If the vacuum continues to drop, remove the power steering pressure line and the power steering return hose from the power steering pump . Refer to Power Steering Pressure Pipe/Hose Replacement .
  2. Install the plugs (1,2) supplied with J 43485
  3. Place the J 35555 on the power steering pump.
  4. Apply a vacuum of 20 Hg maximum.
  5. If the vacuum drops again, repair or replace the power steering pump. Refer to Power Steering Pump Replacement If the vacuum holds steady, continue to check the other parts of the power steering system.
  6. Important: Power steering fluid must be free from bubbles. Be aware of periodic bubbles that indicate a loose connection or leaking O-ring seal in the power steering hoses.

    Important: Power steering fluid must be free from discoloration.

  7. Observe the power steering fluid.
  8. If the condition persists, replace the following parts:
  9. • The return hose clamps
    • The return hose O-rings
    • The pressure hose O-rings
    • The gear cylinder line O-rings
    • The reservoir to pump O-ring
  10. Repeat the bleed procedure from the beginning.
  11. Drive the vehicle approximately 16 kilometers (10 miles) to warm the system to operating temperature. Evaluate vehicle on a smooth flat surface.
  12. To check for noise problems, verify the following items:
  13. • There is smooth power assist.
    • The vehicle operates quietly.
    • The power steering pump maintains the proper power steering fluid level.
    • There is no leaking in the steering system.
    • The fluid is free of foam or discoloration.