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 WarningRear Wheelhouse Liner Replacement (Sedan - Left)
Rear Wheelhouse Liner Replacement
Callout
Component Name
Preliminary Procedure
Remove the tire and wheel assembly. Refer to Tire and Wheel Removal and
Installation.
1
Rear Wheelhouse Panel Liner ...
Engine Front Cover and Oil Pump Installation
Special Tools
EN-952 Fixing Pin
EN-953-A Fixing Tool
EN-49977-100 Transmitter Disc Fixation
EN-49977-200 Fixing Tool
For equivalent regional tools, refer to Special Tools.
Note: Mind the guide sleeves when installing engine front cover.
Install the engine front ...
Oil Pan Removal
Remove the 16 oil pan bolts (1).
Caution: Pry the oil pan carefully in order to prevent damage
to the transaxle case or the oil pan sealing surfaces.
Place a suitable prying tool to the area shown (1) and carefully pry the
oil pan loose.
R ...