Chevrolet 2003 Astro Owner's Manual page 251

If there seems to be no leak, start the engine again.
How to Add Coolant to the Coolant
The engine cooling fan speed should increase when idle
speed is doubled by pushing the accelerator pedal
Recovery Tank
down. If it doesn't, your vehicle needs service. Turn off If you haven't found a problem yet, but the coolant level
the engine.
isn't at the ADD mark, add a 50/50 mixture
of clean
Nofice: Engine damage from running your engine
without coolant isn't covered by your warranty.
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
(50 000 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.
drinkable wafer, and DEX-COOL@ engine coolant at
the coolant recovery tank. See Engine Coolant on
page 5-28 for more information.
Adding only p . , , n water to your coG...rg
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 DEX COOL@ coolant.
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