1994 Chevrolet Suburban Owner's Manual - Page 265

If you cannot find oils with the new "starburst" symbol on the front of the container, you should look for and use oils containing the following three things: SHorSG "SH' or "SG' must be on the oil container, either by itself or combined with other quality designations, such as "SWCD," "SH,SG, CD," "SGKD," etc. These letters show American Petroleum Institute (API) levels of quality. e SAE 5W-30 -Vehicles with Light Duty Emissions (8500 GVWR or less) OR SAE 1OW-30 -Vehicles with more). Energy Conserving I1 Heavy Duty Emissions (8501 GVWR or Oils with these words on the container will help you save fuel. These three things are usually included in a doughnut shaped logo (symbol) on most containers. If you cannot find oils with the "starburst" symbol, you should look for oils with the doughnut shaped symbol, containing the three things noted above. NOTICE: If you use oils that do not have either the "starburst" symbol or an API SH or SG designation, you can cause engine damage not covered by your warranty. GM Goodwrench@oil (in Canada, GM Engine Oil) meets all the requirements for your vehicle. 6-20