Required services for many newer GM vehicles are described by the terms Maintenance I and Maintenance II. The time at which these services are required are determined by the Oil Life System (OLS). When the "Change Oil Soon" message appears this indicates that your vehicle is due for servicing.
Maintenance I will be needed if:
- The "Change Oil Soon" message comes on within 10 months of the vehicle purchase
- When Maintenance II was the last service performed
Maintenance II will be needed if:
- The "Change Oil Soon" message appears and the last service was Maintenance I
Alternate between the two schedules thereafter. Depending upon your driving habits, Maintenance II may be required more often.