See also:

Accessories and Modifications
Adding non-dealer accessories or making modifications to the vehicle can affect vehicle performance and safety, including such things as airbags, braking, stability, ride and handling, emissions syste ...

Engine Air Cleaner/Filter
If the vehicle has a diesel engine, see “Pickup Models” under “Engine Air Cleaner/Filter” in the Duramax® Diesel Supplement for the correct inspection and replacement procedures. See Engine ...

Manual Operation of Power Liftgate
To change the liftgate to manual operation, press OFF on the power liftgate switch. A message displays on the DIC indicating manual operation mode. See Driver Information Center (DIC) (Without DIC B ...