See also:

Maintenance Replacement Parts
Replacement parts identified below by name, part number, or specification can be obtained from your dealer. If your vehicle has a diesel engine, see the Duramax diesel supplement for more informa ...

Add-on Electrical Equipment
The OnStar system is integrated into the electrical architecture of the vehicle. Do not add any electrical equipment. See Add-On Electrical Equipment on page 9‑64. Added electrical equipment ...

Footnotes — Maintenance Schedule Additional Required Services — Normal
a) Or every two years, whichever comes first. More frequent replacement may be needed if the vehicle is driven in areas with heavy traffic, areas with poor air quality, or areas with high dust levels. ...