Page 409 of 562
If Steam Is Coming From Your Engine
{CAUTION:
Steam from an overheated engine can
burn you badly, even if you just open the
hood. Stay away from the engine if you
see or hear steam coming from it. Just
turn it off and get everyone away from the
vehicle until it cools down. Wait until
there is no sign of steam or coolant
before you open the hood.
CAUTION: (Continued)
CAUTION: (Continued)
If you keep driving when your engine is
overheated, the liquids in it can catch re.
You or others could be badly burned.
Stop your engine if it overheats, and get
out of the vehicle until the engine is cool.
Notice:If your engine catches re because
you keep driving with no coolant, your vehicle
can be badly damaged. The costly repairs
would not be covered by your warranty.
409
Page 410 of 562

If No Steam Is Coming From Your
Engine
If you get an engine overheat warning but see or
hear no steam, the problem may not be too
serious. Sometimes the engine can get a little too
hot when you:
Climb a long hill on a hot day.
Stop after high-speed driving.
Idle for long periods in traffic.
Tow a trailer.
If you get the overheat warning with no sign of
steam, try this for a minute or so:
1. In heavy traffic, let the engine idle in
NEUTRAL (N) while stopped. If it is safe to do
so, pull off the road, shift to PARK (P) or
NEUTRAL (N) and let the engine idle.
2. Turn on your heater to full hot at the highest
fan speed and open the windows as
necessary.If you no longer have the overheat warning, you
can drive. Just to be safe, drive slower for
about 10 minutes. If the warning does not come
back on, you can drive normally.
If the warning continues and you have not
stopped, pull over, stop, and park your vehicle
right away.
If there is still no sign of steam, you can push down
the accelerator until the engine speed is about twice
as fast as normal idle speed for at least three
minutes while you are parked. If you still have the
warning, turn off the engine and get everyone out of
the vehicle until it cools down.
You may decide not to lift the hood but to get
service help right away.
410
Page 411 of 562
Cooling System
When you decide it is safe to lift the hood, here is
what you will see:
A. Coolant Recovery Tank
B. Radiator Pressure Cap
C. Engine FanA. Coolant Recovery Tank
B. Radiator Pressure Cap
C. Engine Fan
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.
4.2L L6 Engine
5.3L V8 Engine
411
Page 412 of 562

The coolant level should
be at least up to the
FULL COLD mark. 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 re,
and you could be burned. Get any leak
xed 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
®
may cause premature engine, heater core, or
radiator corrosion. In addition, the engine
coolant could require changing sooner, at
30,000 miles (50 000 km) or 24 months,
whichever occurs rst. Any repairs would not
be covered by your warranty. Always use
DEX-COOL
®(silicate-free) coolant in your
vehicle.
412
Page 413 of 562

How to Add Coolant to the Coolant
Recovery Tank
If you have not found a problem yet, but the
coolant level is not at the FULL COLD mark, add
a 50/50 mixture of clean, drinkable water and
DEX-COOL
®engine coolant at the coolant
recovery tank. SeeEngine Coolant on page 405
for more information.
{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
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.
When the coolant in the coolant recovery tank is
at the FULL COLD mark, start your vehicle.
413
Page 415 of 562