For service and parts needs, visit your dealer. You will receive genuine GM parts and GM-trained and supported service people.
Genuine GM parts have one of these marks:

Vehicle Care
California Proposition 65 WarningRemoval Procedure
Warning: Refer to Approved Equipment for Collision Repair Warning in the
Preface section.
Warning: Refer to Glass and Sheet Metal Handling Warning in the Preface section.
Disable the SIR System. Refer to SIR Disabling and Enabling
Disconnect the negative battery cable. Refer to Batte ...
Power Steering
Specifications
Power Steering System Bleeding
Note:
Use clean, new power steering fluid type only. See the Maintenance
and Lubrication subsection for fluid specifications.
Hoses touching the frame, body or engine may cause system noise.
Verify that the hoses do not touch any ot ...
Steering Linkage Inner Tie Rod Replacement (Hydraulic Power Steering)
Special Tools
CH-6247 Removal and Installation Tool for the Steering Linkage Inner Tie Rod
For equivalent regional tools, refer to Special Tools.
Removal Procedure
Raise and support the vehicle. Refer to Lifting and Jacking the
Vehicle.
Remove the tire and wheel assembly. Refer to ...