Pontiac 2003 Aztek Owner's Manual page 318

Notice: When adding coolant, it is important that
you use only DEX-COOL@ (silicate-free) coolant.
If coolant other than DEX-COOL is added to
the system, premature engine, heater core or
radiator corrosion may result. In addition, the engine
coolant will require change sooner
--
at 30,000 miles
(50,OQQ km) or 24 months, whichever occurs first.
Damage caused by the use of coolant other
than DEX-COOL@ is not covered by your new vehicle
warranty.
What to Use
Use a mixture of one-half clean, drinkable water and
one-half DEX-COOL@ coolant which won't damage
aluminum parts. If you use this coolant mixture,
you don't need to add anything else.
Adding only plain wa.w 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 wouldn't get the overheat warning.
Your engine could catch fire and you or others
could be burned. Use a 50/50 mixture of clean,
drinkable water and D€X-COOL@ coolant.
Notice: If you use an improper coolant mixture,
your engine could overheat and be badly damaged.
The repair cost wouldn't 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.
. I - . . - - .
Nnfima-
If y n ~ use the proper coolantj you
don't
have to add extra inhibitors or additives which claim
to improve the system. These can be harmful.
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