Engine Oil Additives/Engine Oil Flushes
Do not add anything to the oil. The recommended oils with the dexos specification and displaying the dexos certification mark are all that is needed for good performance and engine protection.
Engine oil system flushes are not recommended and could cause engine damage not covered by the vehicle warranty.
See also:
Replacement Bulbs
For replacement bulbs not listed
here, contact your dealer. ...
Service Manuals
Service Manuals have the diagnosis
and repair information on the
engines, transmission, axle,
suspension, brakes, electrical,
steering, body, etc. ...
Cellular and GPS Antennas
Avoid placing items over or near the
antenna to prevent blocking cellular
and GPS signal reception. Cellular
reception is required for OnStar to
send remote signals to the vehicle. ...