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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{CAUTION:
An electric engine cooling fan under the hood
can start up even when the engine is not
running and can injure you. Keep hands,
clothing and tools away from any underhood
electric fan.
If the coolant inside the coolant surge tank is boiling, do
not do anything else until it cools down. The vehicle
should be parked on a level surface. Make sure that the
air conditioning is turned off.
The coolant level should be between the MIN and MAX
marks on the coolant surge tank when the engine is
cool. 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 else 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 is running. If
the engine is overheating, the fan should be running. If
it is not, your vehicle needs service.
Notice:Engine damage from running your engine
without coolant is not covered by your warranty.
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