2002 GMC Yukon Owner's Manual - Page 409

Scheduled Maintenance Engine Oil and Chassis Lubrication Scheduled Maintenance Change engine oil and filter as indicated by the GM Oil Life Systemt (or every 12 months, whichever occurs first). Reset the system. Your vehicle has a computer system that lets you know when to change the engine oil and filter. This is based on engine revolutions and engine temperature, and not on mileage. Based on driving conditions, the mileage at which an oil change will be indicated can vary considerably. For the oil life system to work properly, you must reset the system every time the oil is changed. When the system has calculated that oil life has been diminished, it will indicate that an oil change is necessary. A CHANGE ENGINE OIL message will come on. Change your oil as soon as possible within the next two times you stop for fuel. It is possible that, if you are driving under the best conditions, the oil life system may not indicate that an oil change is necessary for over a year. However, your engine oil and filter must be changed at least once a year and at this time the system must be reset. It is also important to check your oil regularly and keep it at the proper level. If the system is ever reset accidentally, you must change your oil at 3,000 miles (5 000 km) since your last oil change. Remember to reset the oil life system whenever the oil is changed. See "Oil Life System" in the Index for information on resetting the system. An Emission Control Service. Lubricate chassis components with each engine oil and filter change. Lubricate the front suspension, ball joints, steering linkage, transmission shift linkage, transfer case shift linkage, and parking brake cable guides. Ball joints should not be lubricated unless their temperature is 10_F (-12_C) or higher, or they could be damaged. 7-6