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If you are in an area of extreme cold, where the
temperature falls below−20°F (−29°C), it is
recommended that you use either an SAE 5W-30
synthetic oil or an SAE 0W-30 oil. Both provide
easier cold starting and better protection for
the engine at extremely low temperatures.
Engine Oil Additives
Do not add anything to the oil. The recommended
oils with the starburst symbol that meet
GM Standard GM6094M are all you need for
good performance and engine protection.
Engine Oil Life System
When to Change Engine Oil
Your vehicle has a computer system that lets you
know when to change the engine oil and lter.
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 SOON
message will come on. Change the oil 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 oil life system might not indicate
that an oil change is necessary for over a
year. However, the engine oil and lter must be
changed at least once a year and at this time the
system must be reset. Your dealer/retailer has
trained service people who will perform this work
using genuine parts and reset the system. It is
also important to check the oil regularly and keep
it at the proper level.
If the system is ever reset accidentally, you must
change the 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.
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If you no longer have the overheat warning,
you can drive. Just to be safe, drive slower for
about 10 minutes. If the warning does not
come back on, you can drive normally.
If the warning continues, pull over, stop, and park
your vehicle right away.
If there is still no sign of steam, idle the engine for
three 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
This emergency operating mode lets your vehicle
be driven to a safe place in an emergency situation.
If an overheated engine condition exists, an
overheat protection mode which alternates ring
groups of cylinders helps prevent engine damage.
In this mode, there is a signi cant loss in power and
engine performance. The temperature gage
indicates an overheat condition exists. 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 on page 397.
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Rear Drive Module
When to Check Lubricant
Refer to the Maintenance Schedule to determine
how often to check the lubricant. SeeScheduled
Maintenance on page 502.
How to Check Lubricant
To get an accurate reading, the vehicle should be
on a level surface.If the level is below the bottom of the ller plug hole,
you will need to add some lubricant. Add enough
lubricant to raise the level to the bottom of the ller
plug hole. Use care not to overtighten the plug.
What to Use
Refer to the Maintenance Schedule to determine
what kind of lubricant to use. SeeRecommended
Fluids and Lubricants on page 511.
Headlamp Aiming
Headlamp aim has been preset at the factory and
should need no further adjustment.
However, if your vehicle is damaged in an
accident, the headlamp aim may be affected.
Aim adjustment to the low-beam headlamps may
be necessary if oncoming drivers ash their
high-beam headlamps at you (for vertical aim).
If you believe your headlamps need to be
re-aimed, it is recommend that you take the vehicle
to your dealer/retailer for service.
(A) Filler Plug (B) Drain Plug
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