1995 GMC Jimmy Owner's Manual - Page 250

What Kind of Oil to Use Oils of the proper quality for your vehicle can be 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 yourgasoline engine. If you change your own oil, B sure YOU use oil that has the "Starburst" e symbol on the front of the oil container. If you have your oil changed for you, be sure the oil put into your engine is American PetroleumInstitute certified for gasoline engines. 6- 10