1993 Oldsmobile Silhouette Owner's Manual - Page 231

Engine Oil Additives Don't add anything to your oil. Your Oldsmobile dealer is ready to advise if you think something should beadded. When to Change Engine Oil See if any one of these is true for you: Most trips are less than4 miles (6 km). It's below freezing outside and most trips are less than 1 miles (16 km). 0 The engine is at low speed most of the time (as in door-to-door delivery, or in stop-and-go traffic). You tow a trailer often. Most trips are through dusty places. If any one of these is true for your vehicle, then you need to change your oil and filter every 3,000 miles (5 000 km) or 3 months-whichever comes first. If none of them is true, change the oil every 7,500 miles (12 500 km) or 12 months-whichever comes first. Change the filter at the first oil change and at every other oil change after that. Engine Block Heater (omoN) An engine blockheater can be a big help if you have topark outside in very cold weather, 0°F (-18"C) or colder. If your vehicle has this option, see the Index under Engine Block Heater. 229