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What to Use
Use a 50/50 mixture ofclean, drinkable waterand coolant
that meets GM Specification 1825M, which will not
damage aluminum parts. You can also use a recycled
coolant conforming to GM Specification 1825M with a
complete coolant flush and refill. 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 the proper 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 the proper coolant, you do not
have to add extra inhibitors or additives which claim
to improve the system. These can be harmful.
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Checking Coolant
The engine coolant surge tank is located in the rear
of the engine compartment on the driver’s side of
the vehicle. SeeEngine Compartment Overview
on page 5-12for 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 between
the MAX (A) and MIN (B) marks on the coolant surge
tank. The level rises at engine operation temperature
and drops again when the engine cools down.
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Adding Coolant
If the level falls below the MIN (B) mark, add the proper
coolant mixtureat the surge tank,but only when the
engine is cool. If the surge tank is empty, a special
fill procedure is necessary. SeeCooling System
on page 5-26for instructions on “How to Add Coolant
to the Coolant Surge Tank.”
{CAUTION:
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.
When replacing the pressure cap, make sure it is
hand-tight.
Coolant Surge Tank Pressure Cap
Notice:If the pressure cap is not tightly installed,
coolant loss and possible engine damage may
occur. Be sure the cap is properly and tightly
secured.
Engine Overheating
You will find a coolant temperature gage on your
vehicle’s instrument panel cluster. SeeEngine Coolant
Temperature Gage on page 3-23.
If Steam Is Coming From Your Engine
{CAUTION:
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. Just 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 your engine is
overheated, the liquids in it can catch re.
You or others could be badly burned. Stop
your engine if it overheats, and get out of
the vehicle until the engine is cool.
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