2009 Hummer H3T Owner's Manual - Page 338

6-4 Maintenance Schedule If the engine oil life system is ever reset accidentally, service the vehicle within 3,000 miles (5 000 km) since the last service. Remember to reset the oil life system whenever the oil is changed. See Engine Oil Life System on page 5-15 for information on the Engine Oil Life System and resetting the system. When the CHANGE 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 the first service be Maintenance I, the second service be Maintenance II, and then alternate Maintenance I and Maintenance II thereafter. However, in some cases, Maintenance II may be required more often. Maintenance I - Use Maintenance I if the CHANGE OIL message displays within 10 months since the vehicle was purchased or Maintenance II was performed. Maintenance II - Use Maintenance II if the previous service performed was Maintenance I. Always use Maintenance II whenever the message displays 10 months or more since the last service or if the message has not come on at all for one year. Scheduled Maintenance When the CHANGE OIL message displays in the Driver Information Center (DIC), service is required for the vehicle. See DIC Warnings and Messages on page 3-37. Have the vehicle serviced as soon as possible within the next 600 miles (1 000 km). It is possible that, if driving under the best conditions, the engine oil life system may not indicate that vehicle service is necessary for over a year. However, the engine oil and filter must be changed at least once a year and at this time the system must be reset. Your dealer/retailer has trained service technicians who will perform this work using genuine parts and reset the system.