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 WarningValve Guide Reaming, and Valve and Seat Grinding
Valve Cleaning Procedure
Use soft bristle wire brush to clean any carbon build-up from the valve
head. DO NOT use a wire brush on any part of the valve stem. The valve stem
is chrome plated to provide enhanced wear characteristics. Wire brushing
the stem could remove the chr ...
P-Metric Sized Tires Description
245/50r16953typeloadindep-passengerttemporarylt-lighttruckspeedsymbolsectionwidth(millimeters)235245275construction(sectionwidth)ddagonal(bas)40sectionwidthsectionheight
Replacement tires should be of the same tire performance criteria (TPC) specification
number. This will ensure the same size, ...
Intake Manifold Removal
Note: Intake manifold bolts remain in intake manifold screw bores.
Remove the 6 intake manifold bolts (1).
Remove the intake manifold (1) along with the intake manifold gasket.
...