To ensure you are using the recommended oil for your GM car, choose authentic, licensed dexos® oils. dexos® is an exclusive trademark of General Motors. Only those oils displaying the green or blue dexos® trademark and icon on the front label have been certified and licensed by GM as meeting the demanding performance requirements and stringent quality standards of the dexos® specification. Other oils may make claims but have not gone through GM's rigorous testing and quality control process.