1995 GMC Sonoma Owner's Manual - Page 229

NOTICE: Use only engine oil with the American Petroleum Institute Certified For Gasoline Engines "Starburst" symbol. Failure to use the proper oil can result in engine damage not covered by your warranty. GM Goodwrench@ oil Canada, GM Engine Oil) meets all the (in requirements for your vehicle. Engine Oil Additives Don't add anything to your oil. GM dealer is ready advise if you Your to think something should be added. When to Change Engine Oil See if any one of these is true for you: Most trips are less than5 to 10 miles (8 to 16 km). This is particularly important when outside temperatures are below freezing. Most trips include extensive idling (such as frequent driving in stop and go traffic). You operate your vehicle in dusty areas oroff-road frequently. You frequently tow a trailer. If any one of these istrue for your vehicle, then need to change your oil you and filter every 3,000 miles (5 000 km) or 3 months - whichever comes first. and If none of them is true, change the oil filter every7,500 miles (12 500 km) or 12 months -whichever comes first. 6-11