2005 Chevrolet Cobalt Owner's Manual - Page 236

Notice: Use only engine oil identified as meeting GM Standard GM6094M and showing the American Petroleum Institute Certified For Gasoline Engines starburst symbol. Failure to use the recommended oil can result in engine damage not covered by your warranty. GM Goodwrench® oil meets all the requirements for your vehicle. If you are in an area of extreme cold, where the temperature falls below −20°F (−29°C), it is recommended that you use either an SAE 5W-30 synthetic oil or an SAE 0W-30 oil. Both will provide easier cold starting and better protection for your engine at extremely low temperatures. For Vehicles with the 2.0L L4 Supercharged Engine Only Look for two things: • GM4718M Your vehicle's engine requires a special oil meeting GM Standard GM4718M. Oils meeting this standard may be identified as synthetic. However, not all synthetic oils will meet this GM standard. You should look for and use only an oil that meets GM Standard GM4718M. 5-18