The 10 largest oil 1 producers and share of total world oil production 2 in 2018 3 . 1 Oil includes crude oil, all other petroleum liquids, and biofuels. 2 Production includes domestic production of crude oil, all other petroleum liquids, biofuels, and refinery processing gain. In total, about two dozen countries expanded their oil production over the past five years, including Saudi Arabia, Canada, United Arab Emirates, Iraq, Kuwait and Russia. Group V base oils are classified as all other base oils, including silicone, phosphate ester, polyalkylene glycol (PAG), polyolester, biolubes, etc. These base oils are at times mixed with other base stocks to enhance the oil’s properties. An example would be a PAO-based compressor oil that is mixed with a polyolester.