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 WarningFuel and Evaporative Emission Pipe Warning
Warning: In order to reduce the risk of fire and personal injury observe
the following items:
Replace all nylon fuel pipes that are nicked, scratched or damaged
during installation, do not attempt to repair the sections of the
nylon fuel pipes
Do not hammer directly on the fuel harness ...
Tracing Powder or Chalk Test
Clean the weatherstrips and the contact surfaces with cleaning solvent.
Apply powder or chalk in an unbroken line to the contact surface of the
weatherstrip surrounding the perimeter of the suspected
areas.
Close the panel completely without slamming the panel. Closing the panel
comple ...
Strut, Strut Component, or Spring Replacement
Special Tools
CH-6068 Spring Tensioner Device
CH-6066 Holding Device
For equivalent regional tools, refer to Special Tools.
Disassembly Procedure
Remove the strut assembly. Refer to Strut Assembly
Replacement.
Install the strut to the CH-6066 holder (5).
Tens ...