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 WarningCatalytic Converter Heat Shield Replacement (LUV)
Catalytic Converter Heat Shield Replacement
Callout
Component Name
Warning: Refer to Exhaust Service Warning.
1
Catalytic Converter Heat Shield Fasteners (Qty: 4)
Caution: Refer ...
Drive and Driven Sprocket, Drive Link, and Park Pawl Installation (6T40/45/50)
Drive and Driven Sprocket, Drive Link, and Park Pawl Installation
Callout
Component Name
1
Front Differential Carrier Baffle
2
Front Differential Carrier Baffle Bolt M6 x 16& ...
Engine Flywheel Installation
Special Tools
EN-652 Flywheel Holder
EN-45059 Torque Angle Sensor Kit
For equivalent regional tools, refer to Special Tools.
Clean the thread in the crankshaft.
Install the crankshaft position reluctor ring (1).
Install the flywheel (2).
Install the EN-6 ...