Do I have to buy dexos oil from a GM dealership?
The dexos license is sold by General Motors to oil producers. Any manufacturer that buys their license can provide approved oil. GM enforces this by stating it may void the warranty if licensed oil is not used. Not all oil producers are willing to pay GM for the license. Best is to look for the dexos logo or contact the oil company to see if they are licensed. For more information, please read General Motors dexos oil in our Detailed Topics Section.