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What to Use
{WARNING:
Adding only plain water to the cooling system can
be dangerous. Plain water, or some other liquid
such as alcohol, can boil before the proper
coolant mixture will. The vehicle's coolant warning
system is set for the proper coolant mixture. With
plain water or the wrong mixture, the engine could
get too hot but you would not get the overheat
warning. The engine could catch fire and you or
others could be burned. Use a 50/50 mixture of
clean, drinkable water and DEX-COOL®coolant.
Use a 50/50 mixture of clean, drinkable water andDEX-COOL®coolant. If using this mixture, nothingelse needs to be added. This mixture:
.Gives freezing protection down to!34°F (!37°C),outside temperature.
.Gives boiling protection up to 265°F (129°C),engine temperature.
.Protects against rust and corrosion.
.Will not damage aluminum parts.
.Helps keep the proper engine temperature.
Notice:If an improper coolant mixture is used, theengine could overheat and be badly damaged. Therepair cost would not be covered by the vehiclewarranty. Too much water in the mixture can freezeand crack the engine, radiator, heater core, andother parts.
Notice:If extra inhibitors and/or additives are usedin the vehicle's cooling system, the vehicle could bedamaged. Use only the proper mixture of the enginecoolant listed in this manual for the cooling system.SeeRecommended Fluids and Lubricantsonpage 8!10for more information.
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Checking Coolant
The vehicle must be on a level surface when checkingthe coolant level.
Check to see if coolant is visible in the coolant surgetank. If the coolant inside the coolant surge tank isboiling, do not do anything else until it cools down.If coolant is visible but the coolant level is not at orabove the FULL COLD mark, add a 50/50 mixture ofclean, drinkable water and DEX-COOL®coolant at thecoolant surge tank, but be sure the cooling system iscool before this is done.
The coolant surge tank is located in the enginecompartment on the passenger side of the vehicle.SeeEngine Compartment Overviewon page 7!16formore information on location.
The coolant level should be at or above the FULLCOLD mark. If it is not, you may have a leak in thecooling system.
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How to Add Coolant to the Surge Tank
{WARNING:
You can be burned if you spill coolant on hot
engine parts. Coolant contains ethylene glycol
and it will burn if the engine parts are hot enough.
Do not spill coolant on a hot engine.
Notice:This vehicle has a specific coolant fillprocedure. Failure to follow this procedure couldcause the engine to overheat and be severelydamaged.
{WARNING:
An electric engine cooling fan under the hood can
start up even when the engine is not running and
can cause injury. Keep hands, clothing, and tools
away from any underhood electric fan.
{WARNING:
Steam and scalding liquids from a hot cooling
system can blow out and burn you badly. They are
under pressure, and if you turn the surge tank
pressure cap—even a little—they can come out
at high speed. Never turn the cap when the
cooling system, including the surge tank pressure
cap, is hot. Wait for the cooling system and surge
tank pressure cap to cool if you ever have to turn
the pressure cap.
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If no coolant is visible in the surge tank, add coolantas follows:
1. You can remove thecoolant surge tankpressure cap whenthe cooling system,including the coolantsurge tank pressurecap and upper radiatorhose, is no longer hot.
Turn the pressure cap slowly counterclockwiseabout one full turn. If you hear a hiss, wait forthat to stop. A hiss means there is still somepressure left.
2. Keep turning the pressure cap slowly andremove it.
3. Fill the coolant surge tank with the proper mixtureto the FULL COLD mark.
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4. With the coolant surge tank pressure cap off, startthe engine and let it run until you can feel theupper radiator hose getting hot. Watch out for theengine cooling fan.
By this time, the coolant level inside the coolantsurge tank may be lower. If the level is lower, addmore of the proper mixture to the coolant surgetank until the level reaches the FULL COLD mark.
5. Replace the pressure cap. Be sure the pressurecap is hand-tight and fully seated.
6. Verify coolant level after engine is shut off and thecoolant is cold. If necessary, repeat coolant fillprocedure Steps 1 through 6.
Notice:If the pressure cap is not tightly installed,coolant loss and possible engine damage mayoccur. Be sure the cap is properly and tightlysecured.
Engine Overheating
The vehicle has several indicators to warn of engineoverheating.
There is a coolant temperature gage on your vehicle'sinstrument panel. SeeEngine Coolant TemperatureGage on page 4!35.
In addition, ENGINE OVERHEATED STOP ENGINE,ENGINE OVERHEATED IDLE ENGINE, and a ENGINEPOWER IS REDUCED message comes on in the DriverInformation Center (DIC) on the instrument panel. SeeDIC Warnings and Messages on page 4!48.
You may decide not to lift the hood when this warningappears, but instead get service help right away. SeeRoadside Service on page 9!8.
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If you do decide to lift the hood , make sure the vehicleis parked on a level surface.
Then check to see if the engine cooling fans arerunning. If the engine is overheating, both fans shouldbe running. If they are not, do not continue to run theengine and have the vehicle serviced.
Notice:Engine damage from running your enginewithout coolant is not covered by your warranty.SeeOverheated Engine Protection Operating Modeon page 7!37for information on driving to a safeplace in an emergency.
Notice:If the engine catches fire while driving withno coolant, the vehicle can be badly damaged. Thecostly repairs would not be covered by the vehiclewarranty. SeeOverheated Engine ProtectionOperating Modeon page 7!37for information ondriving to a safe place in an emergency.
If Steam Is Coming From The Engine
Compartment
{WARNING:
Steam from an overheated engine can burn you
badly, even if you just open the hood. Stay away
from the engine if you see or hear steam coming
from it. Turn it off and get everyone away from the
vehicle until it cools down. Wait until there is no
sign of steam or coolant before you open
the hood.
If you keep driving when the vehicles engine is
overheated, the liquids in it can catch fire. You or
others could be badly burned. Stop the engine if it
overheats, and get out of the vehicle until the
engine is cool.
SeeOverheated Engine Protection Operating
Modeon page 7!37for information on driving to
a safe place in an emergency.
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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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If you need to replace any of your wheels, wheel bolts,wheel nuts, or Tire Pressure Monitor System (TPMS)sensors, replace them only with new GM originalequipment parts. This way, you will be sure to havethe right wheel, wheel bolts, wheel nuts, and TPMSsensors for your vehicle.
{WARNING:
Using the wrong replacement wheels, wheel bolts,
or wheel nuts on your vehicle can be dangerous.
It could affect the braking and handling of your
vehicle, make your tires lose air and make you
lose control. You could have a collision in which
you or others could be injured. Always use the
correct wheel, wheel bolts, and wheel nuts for
replacement.
Notice:The wrong wheel can also cause problemswith bearing life, brake cooling, speedometer orodometer calibration, headlamp aim, bumper height,vehicle ground clearance, and tire or tire chainclearance to the body and chassis.
SeeChanging a Flat Tireon page 7!80for moreinformation.
Used Replacement Wheels
{WARNING:
Putting a used wheel on the vehicle is dangerous.
You cannot know how it has been used or how
far it has been driven. It could fail suddenly and
cause a crash. If you have to replace a wheel,
use a new GM original equipment wheel.
Tire Chains
{WARNING:
Do not use tire chains. There is not enough
clearance. Tire chains used on a vehicle without
the proper amount of clearance can cause
damage to the brakes, suspension, or other
vehicle parts. The area damaged by the tire
chains could cause you to lose control of the
vehicle and you or others may be injured in a
crash. Use another type of traction device only if
its manufacturer recommends it for use on the
(Continued)
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