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:
Trademarks and License Agreements
Manufactured under license under U.S. Patent #'s: 5,451,942; 5,956,674; 5,974,380;
5,978,762; 6,487,535 & other U.S. and worldwide patents issued & pending. DTS and
the Symbol are re ...
Online Owner Center
GMC Owner Center (U.S.) www.gmcownercenter.com
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Potential Issues
Some OnStar services are disabled after five days. OnStar cannot perform Remote Door Unlock or Stolen Vehicle Assistance after the vehicle has been off continuously for five days. After five days, OnS ...