1995 GMC Safari Owner's Manual - Page 216

What Kind of Oil to Use Oils of the proper qualityfor your vehicle canbe identified by looking for the "Starburst" symbol. The "Starburst" symbol indicates that the oil has been certified by the American Petroleum Institute (API), and is preferred for use in your gasoline engine. If you change your own oil, be sure you use oil that has "Starburst" the symbol on the front of the oil container.If you have youroil changed for you, be sure the oil put into your engine is American Petroleum Institute certified for gasoline engines. 6 - 1.0