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 WarningRear Side Door Check Replacement
Preliminary Procedure
Remove rear side door trim panel. Refer to Rear Side Door
Trim Replacement
Remove the rear side door water deflector. Refer to Rear Side Door Water
Deflector Replacement
Rear Side Door Check Bolt
Caution: Refer to Fastener Caution in the Pre ...
Reduced Engine Power Light
The reduced engine power light should come on briefly as the engine is started.
If it does not come on, have the vehicle serviced by your dealer.
This light, along with the malfunction indicator lamp, displays when a noticeable
reduction in the vehicle's performance occurs. Stop the vehic ...
SIR Service Precautions
SIR Service Precautions
Warning: When performing service on or near the SIR components or
the SIR wiring, the SIR system must be disabled. Failure to observe
the correct procedure could cause deployment of the SIR components. Serious
injury can occur. Failure to observe the correct procedure
...