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:

California Proposition 65 WarningBrake Warning System Description and Operation
Brake Warning Indicator
Brake Warning Block Diagram
B80Park
Brake
SwitchB20Brake
Fluid Level
SwitchK9Body
Control
ModuleP16Instrument
Cluster
Hard-Wired
Seri ...
Radiator Grille Opening Cover Replacement (Upper Grille Cover)
Radiator Grille Opening Cover Replacement
Callout
Component Name
Preliminary Procedure
Remove the radiator upper grille. Refer to Front Upper Grille Replacement.
1
Radiator Grille Opening Cover ( ...
Rear Window Washer Nozzle Replacement
Rear Window Washer Nozzle Replacement
Callout
Component Name
Preliminary Procedure
Remove the inside high mount stop lamp. Refer to High Mount Stop Lamp
Replacement.
1
Rear Window Washer Nozzle
...