GM Service Manual Online
For 1990-2009 cars only

Notice: If the power steering system has been serviced, an accurate fluid level reading cannot be obtained unless air is bled from the steering system. The air in the fluid may cause pump cavitation noise and may cause pump damage over a period of time.

Bleed the power steering system under the following conditions:

    • After replacing any component
    • After disconnecting the fluid line
    • After servicing the power steering hydraulic system
    • In order to correct steering system noise

Bleed the power steering system in order to prevent the following conditions:

    • Damage to the pump
    • Improper system operation
    • Steering system noise

Prior to Bleeding the Power Steering System

Inspect the power steering system prior to bleeding the system. Verify that the following conditions apply:

   • 
Object Number: 102169  Size: SH
  • The power steering hoses are not touching any other part of the vehicle.
  •    • 
  • The steering system noise is not caused by a hose touching any of the following:
  •    - The frame
       - The body
       - The engine
       • 
    Object Number: 102174  Size: SH
  • The hose connections are tight.
  •    • 
  • Loose connections are not allowing air into the system.
  • Special Conditions

    If a problem still exists after bleeding the power steering system, proceed as follows:


      Object Number: 105115  Size: SH
    1. Ensure the power steering fluid is free of foam or bubbles. Periodic bubbles found during Step 7 of bleeding the power steering system may indicate the following conditions:
    2. • A loose connection in either the return hose or the pressure hose.
      • A leaky O-ring seal in either the return hose or the pressure hose.
    3. Inspect the power steering fluid for a milky, opaque, or light tan discoloration.
    4. If the fluid is discolored or bubbles appear in the fluid, perform the following procedure:

      2.1. Turn the ignition switch to the OFF position.
      2.2. Wait 2 minutes.
      2.3. Repeat steps 9-15 of bleeding the power steering system. If a problem continues, inspect and replace any of the following defective components:
         • The return hose clamps
         • The return hose O-rings
         • The pressure hose O-rings
         • The gear cylinder line O-rings
      2.4. Fill the power steering system.
      2.5. After replacing any defective components, repeat steps 9-15 in order to verify the condition is corrected.

      Object Number: 105117  Size: SH
    5. Inspect the power steering pump for a whining or groaning noise.
    6. If a noise is heard, run the engine. Ensure the hoses are not contacting the frame body or the engine.

    7. Cool down the fluid and repressurize the power steering system by performing either of the following methods:

    Method 1: Normal Cool Down

      4.1. Turn the engine off.
      4.2. Wait for the system to cool.
      4.3. Install the reservoir cap.

    Method 2: Partial Fluid Replacement

      4.1. Turn the engine off.
      4.2. Remove the fluid from the reservoir using a suction device.
      4.3. Refill the system with cool, clean fluid.
      4.4. Install the reservoir cap.
    1. Start the engine.
    2. Allow the engine to reach the normal operating temperature.
    3. If any noise continues, remove and replace the power steering pump. Refer to Power Steering Pump Replacement .
    4. After replacing the power steering pump, bleed the power steering system again.