Chevrolet 2005 Astro Owner's Manual page 243

If the coolant inside the coolant recovery tank is boiling,
do not do anything else until it cools down. The
vehicle should be parked on a level surface.
The coolant level should be at the ADD mark if the
engine is cold, or the FULL HOT mark if the engine is
warm. 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 fire, and you could be
burned. Get any leak fixed before you drive
the vehicle.
If there seems to be no leak, start the engine again.
The engine cooling fan speed should increase when
idle speed is doubled by pushing the accelerator pedal
down. If it does not, your vehicle needs service.
Turn off the engine.
Notice: Engine damage from running your engine
without coolant is not covered by your warranty.
Notice: Using coolant other than DEX-COOL
cause premature engine, heater core or radiator
corrosion. In addition, the engine coolant may
require changing sooner, at 30,000 miles (50 000 km)
or 24 months, whichever occurs first. Any repairs
would not be covered by your warranty. Always use
®
DEX-COOL (silicate-free) coolant in your vehicle.
®
may
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