Scheduled MaintenanceWhen the Change Engine Oil message in the DriverInformation Center (DIC) comes on, it means thatservice is required for your vehicle. Have your vehicleserviced as soon as possible within the next 600 miles(1 000 km). It is possible that, if you are drivingunder the best conditions, the engine oil life system maynot indicate that vehicle service is necessary for overa year. However, your engine oil and filter must bechanged at least once a year and at this time the systemmust be reset. Your GM Goodwrench dealer hasGM-trained service technicians who will perform thiswork using genuine GM parts and reset the system.If the engine oil life system is ever reset accidentally,you must service your vehicle within 3,000 miles(5 000 km) since your last service. Remember to resetthe oil life system whenever the oil is changed.SeeEngine Oil on page 5-16 for information on theEngine Oil Life System and resetting the system.When the Change Engine Oil message appears,certain services, checks and inspections are required.Required services are described in the following for“Maintenance I” and “Maintenance II.” Generally,it is recommended that your first service beMaintenance I, your second service be Maintenance IIand that you alternate Maintenance I and Maintenance IIthereafter. However, in some cases, Maintenance IImay be required more often.Maintenance I — Use Maintenance I if the changeengine oil message comes on within ten months sincevehicle was purchased or Maintenance II wasperformed.Maintenance II — Use Maintenance II if the previousservice performed was Maintenance I. Always useMaintenance II whenever the message comes on tenmonths or more since the last service or if the messagehas not come on at all for one year.6-4