Buick 2001 Century Owner's Manual page 321

Scheduled Maintenance
Engine Oil Scheduled Maintenance
Change engine oil and filter as indicated by
t
the GM Oil Life System
whichever occurs first). Reset the system. The system
will show you when to change the oil
3,000 miles (5 000 km) and 10,000 miles (16 000 km)
since your last oil change. Under severe conditions, the
indicator may come on before 3,000 miles (5 000 km).
Never drive your vehicle more than 10,000 miles
(16 000 km) or 12 months without an oil and
filter change.
7-6
(or every 12 months,
--
usually between
The system won't detect dust in the oil. So if you
drive in a dusty area, be sure to change your oil and
filter every 3,000 miles (5 000 km) or sooner if the
CHANGE OIL SOON light appears. Remember to
reset the Oil Life System when the oil and filter have
been changed. See "Oil Life System" in the Index
for information on resetting.
An Emission Control Service.