1993 Buick LeSabre Owner's Manual - Page 283

Selecting the Right Schedule First you'll need to decide which the two schedules is of right for your vehicle. Here's how to decide which schedule to follow: If any one (or more) of theseis true for your driving, follow Schedule I. Schedule I Is any oneof these true for your vehicle? 0 Most trips are less than 4 miles (6 km). 0 Most trips are less than 10 miles ( 16 km)when outside temperaturesare below freezing. The engine is at low speed most of the time (as in door-to-door delivery,or in stop-and-go traffic). 0 0 Schedule I1 Follow Schedule I1 only if none of the above conditions is true. You operate your vehicle in dusty areas. Youtow a trailer. 281