You could also add that there are other oils that also meet the specs and list them on their labels, but have decided not to pay GM or spend the time to get on their list.quote:Originally posted by Trajan:
The list of approved oils is a list of oils that meet all the specs. Nothing more or less.
Here is what GM says about motor oil:quote:Originally posted by Trajan:They can, and do, require whatever oil you use to meet said specs for warranty coverage.
“The New Vehicle Warranty would not be void simply because an owner failed to use proper engine oils or did not perform maintenance at the prescribed intervals. Warranty applicability is contingent upon the cause of failure.”
Service Policies and Procedures Department,
General Motors Corporation “