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Engine Oil Additives / Engine Oil
Flushes
Do not add anything to the oil. The recommended oilswith the starburst symbol that meet GM standards areall that is needed for good performance and engineprotection.
Engine oil system flushes are not recommended andcould cause engine damage not covered by the vehiclewarranty.
Engine Oil Life System
When to Change Engine Oil
This vehicle has a computer system that indicates whento change the engine oil and filter. This is based onengine revolutions and engine temperature, and not onmileage. Based on driving conditions, the mileage atwhich an oil change is indicated can vary considerably.For the oil life system to work properly, the system mustbe reset every time the oil is changed.
When the system has calculated that oil life has beendiminished, it indicates that an oil change is necessary.A CHANGE ENGINE OIL SOON message comes on.SeeDIC Warnings and Messageson page 4!48.Change the oil as soon as possible within the next600 miles (1 000 km). It is possible that, if driving underthe best conditions, the oil life system might not indicatethat an oil change is necessary for over a year.However, the engine oil and filter must be changed atleast once a year and at this time the system must bereset. Your dealer/retailer has trained service peoplewho will perform this work using genuine parts andreset the system. It is also important to check the oilregularly and keep it at the proper level.
If the system is ever reset accidentally, the oil must bechanged at 3,000 miles (5 000 km) since the last oilchange. Remember to reset the oil life systemwhenever the oil is changed.
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How to Reset the Engine Oil Life
System
The Engine Oil Life System calculates when to changethe engine oil and filter based on vehicle use.Whenever the oil is changed, reset the system so it cancalculate when the next oil change is required. If asituation occurs where the oil is changed prior to aCHANGE ENGINE OIL SOON message being turnedon, reset the system.
Always reset the engine oil life to 100% after every oilchange. It will not reset itself. To reset the Engine OilLife System:
1. Display the OIL LIFE REMAINING on the DIC.
2. Press and hold the SET/RESET button on the DICfor more than five seconds. The oil life will changeto 100%.
If the CHANGE ENGINE OIL SOON message comesback on when the vehicle is started, the Engine Oil LifeSystem has not reset. Repeat the procedure.
What to Do with Used Oil
Used engine oil contains certain elements that can beunhealthy for your skin and could even cause cancer.Do not let used oil stay on your skin for very long. Cleanyour skin and nails with soap and water, or a good handcleaner. Wash or properly dispose of clothing or ragscontaining used engine oil. See the manufacturer'swarnings about the use and disposal of oil products.
Used oil can be a threat to the environment. If youchange your own oil, be sure to drain all the oil from thefilter before disposal. Never dispose of oil by putting it inthe trash, pouring it on the ground, into sewers, or intostreams or bodies of water. Recycle it by taking it to aplace that collects used oil.
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Overheated Engine Protection
Operating Mode
If an overheated engine condition exists and theENGINE POWER IS REDUCED message is displayed,an overheat protection mode which alternates firinggroups of cylinders helps prevent engine damage. Inthis mode, you will notice a loss in power and engineperformance. This operating mode allows the vehicle tobe driven to a safe place in an emergency. Drivingextended miles (km) and/or towing a trailer in theoverheat protection mode should be avoided.
Notice:After driving in the overheated engineprotection operating mode, to avoid engine damage,allow the engine to cool before attempting anyrepair. The engine oil will be severely degraded.Repair the cause of coolant loss, change the oil andreset the oil life system. SeeEngine Oilonpage 7!17.
Engine Fan Noise
The vehicle has electric cooling fans. You might hearthe fans spinning at low speed during most everydaydriving. The fans can turn off if no cooling is required.Under heavy vehicle loading, trailer towing, and/or highoutside temperatures, or if you are operating the airconditioning system, the fans can change to high speedand you might hear an increase in fan noise. This isnormal and indicates that the cooling system isfunctioning properly. The fans change to low speedwhen additional cooling is no longer required.
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At your General Motors dealer/retailer, you can becertain that you will receive the highest level of serviceavailable. Your dealer/retailer has specially trainedservice technicians, uses genuine GM replacementparts, as well as, up to date tools and equipment toensure fast and accurate diagnostics.
The proper replacement parts, fluids, and lubricants touse are listed inRecommended Fluids and Lubricantson page 8!10andMaintenance Replacement Partsonpage 8!12. We recommend the use of genuine partsfrom your dealer/retailer.
Rotation of New Tires
To maintain ride, handling, and performance of thevehicle, it is important that the first rotation service fornew tires be performed when they have 8 000 to13 000 km (5,000 to 8,000 miles). SeeTire Inspectionand Rotation on page 7!71.
Scheduled Maintenance
When the Change Engine Oil Soon
Message Displays
Change engine oil and filter. SeeEngine Oilonpage 7!17.An Emission Control Service.
When the Change Engine Oil Soon message displays,service is required for the vehicle as soon as possible,within the next 1 000 km/600 miles. If driving under thebest conditions, the engine oil life system might notindicate the need for vehicle service for more than ayear. The engine oil and filter must be changed at leastonce a year and the oil life system must be reset. Yourdealer/retailer has trained service technicians who willperform this work and reset the system. If the engine oillife system is reset accidentally, service the vehiclewithin 5 000 km/3,000 miles since the last service. Resetthe oil life system whenever the oil is changed. SeeEngine Oil Life System on page 7!20.
When the Change Engine Oil Soon message displays,certain services, checks, and inspections are required.
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