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Engine Oil Life System
When to Change Engine Oil (Vehicles
With Driver Information Center)
If your vehicle has a Driver Information Center
(DIC), it has the Engine Oil Life System, 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 OIL SOON message
will come on. SeeDIC Warnings and Messages on
page 148. 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 may 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 has GM-trained service
people who will perform this work using genuine
GM parts and reset the system. 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 the oil at 3,000 miles (5 000 km) since
the last oil change. Remember to reset the oil life
system whenever the oil is changed.
How to Reset the Engine Oil Life
System
The Engine Oil Life System calculates when to
change your engine oil and lter based on vehicle
use. Anytime your oil is changed, reset the
system so it can calculate when the next oil
change is required. If a situation occurs where you
change your oil prior to a CHANGE OIL SOON
message being turned on, reset the system.
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What to Use
Use a mixture of one-half clean, drinkable water
and one-half DEX-COOL®coolant which will
not damage aluminum parts. If you use this coolant
mixture, you do not need to add anything else.
{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can
boil before the proper coolant mixture will.
Your vehicle’s coolant warning system is
set for the proper coolant mixture. With
plain water or the wrong mixture, your
engine could get too hot but you would
not get the overheat warning. Your engine
could catch re and you or others could
be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
®coolant.Notice:If you use an improper coolant
mixture, your engine could overheat and be
badly damaged. The repair cost would not be
covered by your warranty. Too much water
in the mixture can freeze and crack the engine,
radiator, heater core, and other parts.
If you have to add coolant more than four times a
year, have your dealer check your cooling
system.
Notice:If you use extra inhibitors and/or
additives in your vehicle’s cooling system,
you could damage your vehicle. Use only the
proper mixture of the engine coolant listed
in this manual for the cooling system. See
Part D: Recommended Fluids and Lubricants
on page 353for more information.
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Checking Coolant
The coolant surge tank is located in the engine
compartment on the driver’s side of the vehicle.
SeeEngine Compartment Overview on page 244
for more information on location.
{CAUTION:
Turning the surge tank pressure cap when
the engine and radiator are hot can allow
steam and scalding liquids to blow out
and burn you badly. Never turn the surge
tank pressure cap — even a little — when
the engine and radiator are hot.
The vehicle must be on a level surface. When
your engine is cold, the coolant level should be at
the COLD FILL line.
Do not over ll the surge tank. Too much coolant
can result in an over ow condition when the uid
is hot.
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The coolant level should be at the COLD FILL line.
If it is not, you may have a leak at the pressure cap
or in the radiator hoses, heater hoses, radiator,
water pump, or somewhere in the cooling system.
{CAUTION:
Heater and radiator hoses, and other
engine parts, can be very hot. Do not touch
them. If you do, you can be burned.
Do not run the engine if there is a leak.
If you run the engine, it could lose all
coolant. That could cause an engine re,
and you could be burned. Get any leak
xed before you drive the vehicle.
If there seems to be no leak, with the engine on,
check to see if the electric engine cooling fan
are running. If the engine is overheating, the fan
should be running. If they are not, your vehicle
needs service.Notice:Engine damage from running your
engine without coolant is not covered by your
warranty.
Notice:Using coolant other than DEX-COOL
®
may cause premature engine, heater core,
or radiator corrosion. In addition, the engine
coolant could require changing sooner, at
30,000 miles (50 000 km) or 24 months,
whichever occurs rst. Any repairs would not
be covered by your warranty. Always use
DEX-COOL
®(silicate-free) coolant in your
vehicle.
How to Add Coolant to the Coolant
Surge Tank
Notice:Your engine has a speci c cooling
system drain and ll procedure. Failure
to follow this procedure could cause your
engine to overheat and be severely damaged.
If your engine’s cooling system needs to
be drained and re- lled, please see your dealer.
If you have not found a problem yet, check to
see if coolant is visible in the coolant surge tank.
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