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If the warning continues, pull over, stop, and park
your vehicle immediately.
If there is still no sign of steam and your vehicle
has an engine-driven cooling fan, push down
the accelerator until the engine speed is about
twice as fast as normal idle speed for at least
ve minutes while you are parked.
If there is still no sign of steam and your vehicle
has an electric cooling fan, idle the engine for
ve minutes while you are parked.
If you still have the warning, turn off the engine
and get everyone out of the vehicle until it
cools down. Also, see “Overheated Engine
Protection Operating Mode” later in this section.
You may decide not to lift the hood but to get
service help right away.Overheated Engine Protection
Operating Mode (V8 Engines Only)
If an overheated engine condition exists and
the REDUCED ENGINE POWER message
is displayed, an overheat protection mode which
alternates ring groups of cylinders helps
prevent engine damage. In this mode, you will
notice a loss in power and engine performance.
This operating mode allows your vehicle to
be driven to a safe place in an emergency. Driving
extended miles (km) and/or towing a trailer in
the overheat protection mode should be avoided.
Notice:After driving in the overheated
engine protection operating mode, to avoid
engine damage, allow the engine to cool before
attempting any repair. The engine oil will be
severely degraded. Repair the cause of coolant
loss, change the oil and reset the oil life
system. SeeEngine Oil (Gasoline Engine) on
page 502.
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If you want to purchase service information, see
Service Publications Ordering Information on
page 666.
Owner Checks and Services on page 635tells you
what should be checked, when to check it, and
what you can easily do to help keep your vehicle in
good condition.
The proper replacement parts, uids, and
lubricants to use are listed inRecommended
Fluids and Lubricants on page 639andNormal
Maintenance Replacement Parts on page 642.
When your vehicle is serviced, make sure these
are used. All parts should be replaced and all
necessary repairs done before you or anyone else
drives the vehicle. We recommend the use of
genuine GM parts.Scheduled Maintenance
(Gasoline Engine)
This maintenance section applies to vehicles with
a gasoline engine. If your vehicle has a diesel
engine, see the maintenance schedule section in
the DURAMAX
®Diesel Engine Supplement.
When the CHANGE ENGINE OIL SOON message
comes on, it means that service is required for your
vehicle. Have your vehicle serviced as soon as
possible within the next 600 miles (1 000 km). It is
possible that, if you are driving under the best
conditions, the engine oil life system may not
indicate that vehicle service is necessary for over a
year. However, your engine oil and lter must be
changed at least once a year and at this time the
system must be reset. Your GM Goodwrench
®
dealer has GM-trained service technicians who will
perform this work using genuine GM parts and reset
the system.
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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 reset the oil life system whenever
the oil is changed. SeeEngine Oil Life System on
page 505for information on the Engine Oil Life
System and resetting the system.
When the CHANGE ENGINE OIL SOON message
appears, certain services, checks, and inspections
are required. Required services are described
in the following for “MaintenanceI” and
“MaintenanceII.” Generally, it is recommended
that your rst service be MaintenanceI, your
second service be MaintenanceII, and that you
alternate MaintenanceIand MaintenanceII
thereafter. However, in some cases,
MaintenanceIImay be required more often.MaintenanceI— Use MaintenanceIif the
CHANGE ENGINE OIL SOON message comes on
within 10 months since the vehicle was purchased
or MaintenanceIIwas performed.
MaintenanceII— Use MaintenanceIIif the
previous service performed was MaintenanceI.
Always use MaintenanceIIwhenever the message
comes on 10 months or more since the last
service or if the message has not come on at all
for one year.
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