Buick 2006 LaCrosse Owner's Manual page 325

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.
When the engine is cold, the coolant level should be
at or above the cold fill line on the coolant recovery tank.
If it is not, there may be 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, with the engine on, check
to see if the electric engine cooling fans are running.
If the engine is overheating, the fans should be running.
If the fans are not running, the vehicle needs service.
Notice: Engine damage from running your engine
without coolant is not covered by your warranty.
See Overheated Engine Protection Operating Mode
on page 5-29 for information on driving to a safe
place in an emergency.
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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