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3. Fill the coolant surge tank with the proper
DEX-COOL®coolant mixture, to slightly
above the FULL COLD/FROID line on the
side of the coolant surge tank.
4. With the coolant surge tank pressure cap off,
start the engine and let it run until you can
feel the upper radiator hose getting hot. The
upper radiator hose is the largest of the
hoses which comes out of the radiator, on the
passenger side of the vehicle. Watch out
for the engine cooling fans.By this time, the coolant level inside the
coolant surge tank may be lower. If the level
is lower, add more of the proper mixture
to the coolant surge tank until the level
reaches the FULL COLD/FROID line on the
side of the coolant surge tank.
5. Then replace the pressure cap. Be sure the
pressure cap is hand-tight and fully seated.
Start the engine and allow it to warm up.
How to Add Coolant to the Intercooler
System Fill Neck (4.4L V8 STS-V
Engine Only)
If you have not found a problem yet, turn the
engine off and allow it to cool down, then check to
see if coolant is visible within the horizontal
tube section of the ll neck. If coolant is not visible,
add a 50/50 mixture of clean, drinkable water
and DEX-COOL
®coolant to the ll neck. Be sure
the Intercooler System, including the Intercooler
System pressure cap, is cool before doing so. See
Engine Coolant on page 389for more information.
400
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{CAUTION:
Turning the Intercooler System pressure
cap when the engine and intercooler are
hot can allow steam and scalding liquids
to blow out and burn you badly. Never
turn the Intercooler System pressure cap,
even a little, when the engine and
intercooler are hot.
{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
CAUTION: (Continued)
CAUTION: (Continued)
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 DEX-COOL
®coolant.
Notice:In cold weather, water can freeze and
crack the engine, radiator, heater core and
other parts. Use the recommended coolant and
the proper coolant mixture.
{CAUTION:
You can be burned if you spill coolant on
hot engine parts. Coolant contains
ethylene glycol and it will burn if the
engine parts are hot enough. Do not spill
coolant on a hot engine.
401
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1. Remove the Intercooler System pressure cap
when the Intercooler System, including the
upper intercooler hoses, are no longer
hot. Turn the pressure cap slowly
counterclockwise about one-quarter of a turn.
If you hear a hiss, wait for that to stop.
This allows any pressure still left to be vented.
2. Then keep turning the pressure cap slowly,
and remove it.3. Add the proper DEX-COOL
®coolant mixture
to the ll neck, until the coolant reaches the
COLD FILL line on the ll neck.
4. With the Intercooler System pressure cap off,
start the engine and let it run for a couple of
minutes. Then turn the engine off. By this time,
the coolant level inside the ll neck may be
lower. If the level drops to where coolant is no
longer visible in the horizontal tube section
of the ll neck, with the engine off add more of
the DEX-COOL
®coolant mixture to the ll
neck until the level is again visible in the
horizontal tube section.
5. Then replace the pressure cap. Be sure the
pressure cap is hand-tight and fully seated.
If the coolant is not at the proper level
when the system cools down again, see
your dealer.
402
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