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Checking the Fluid Level
Prepare your vehicle as follows:
1. Park your vehicle on a level place. Keep the
engine running.
2. With the parking brake applied, place the shift
lever in PARK (P).
3. With your foot on the brake pedal, move the
shift lever through each gear range, pausing
for about three seconds in each range.
Then, position the shift lever in PARK (P).
4. Let the engine run at idle for three minutes
or more.
Then, without shutting off the engine, follow
these steps:
The transmission
dipstick is located near
the center of the
engine compartment
and will be labeled with
the graphic shown.SeeEngine Compartment Overview on page 296
for more information on location.
1. Flip the handle up and then pull out the
dipstick and wipe it with a clean rag or
paper towel.
2. Push it back in all the way, wait three seconds
and then pull it back out again.
3. Check both sides of the dipstick, and read the
lower level. The fluid level must be in the
COLD area for a cold check or in the HOT or
cross-hatched area for a hot check. Be
sure to keep the dipstick pointed down to get
an accurate reading.
4. If the fluid level is in the acceptable range,
push the dipstick back in all the way; then
flip the handle down to lock the dipstick
in place.
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How to Add Automatic
Transmission Fluid
Refer to the Maintenance Schedule to determine
what kind of transmission fluid to use. See
Recommended Fluids and Lubricants on page 409.
Using a funnel, add fluid down the transmission
dipstick tube only after checking the transmission
fluid while it is hot. A cold check is used only
as a reference. If the fluid level is low, add only
enough of the proper fluid to bring the level up to
the HOT area for a hot check. It does not take
much fluid, generally less than one pint (0.5 L). Do
not overfill.
Notice:Use of the incorrect automatic
transmission uid may damage your vehicle,
and the damages may not be covered by
your warranty. Always use the automatic
transmission uid listed inRecommended
Fluids and Lubricants on page 409.
•After adding fluid, recheck the fluid level as
described under “How to Check Automatic
Transmission Fluid,” earlier in this section.
•When the correct fluid level is obtained, push
the dipstick back in all the way; then flip the
handle down to lock the dipstick in place.
Engine Coolant
The cooling system in your vehicle is filled with
DEX-COOL®engine coolant. This coolant is
designed to remain in your vehicle for five years or
150,000 miles (240 000 km), whichever occurs first,
if you add only DEX-COOL
®extended life coolant.
The following explains your cooling system and
how to add coolant when it is low. If you have a
problem with engine overheating, seeEngine
Overheating on page 309.
A 50/50 mixture of clean, drinkable water and
DEX-COOL
®coolant will:
•Give freezing protection down to
−34°F (−37°C).
•Give boiling protection up to 265°F (129°C).
•Protect against rust and corrosion.
•Help keep the proper engine temperature.
•Let the warning lights and gages work as
they should.
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Notice:Using coolant other than DEX-COOL®
may cause premature engine, heater core,
radiator and fuel operated heater (FOH)
corrosion. In addition, the engine coolant may
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.
What to Use
Use a mixture of one-half clean, drinkable water
and one-half DEX-COOL®coolant which will
not damage aluminum parts. If you use this coolant
mixture, you do not need to add anything else.
{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.
CAUTION: (Continued)
CAUTION: (Continued)
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 the proper coolant.
Notice:If you use an improper coolant
mixture, your engine could overheat and be
badly damaged. The repair cost would not be
covered by your warranty. Too much water
in the mixture can freeze and crack the engine,
radiator, heater core, and other parts.
If you have to add coolant more than four times a
year, have your dealer check your cooling system.
Notice:If you use extra inhibitors and/or
additives in your vehicle’s cooling system, you
could damage your vehicle. Use only the proper
mixture of the engine coolant listed in this
manual for the cooling system. See
Recommended Fluids and Lubricants on
page 409for more information.
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Checking Coolant for Gasoline Engines
If your vehicle has a diesel engine, see “Checking
Coolant” under “Van Models” in the DURAMAX®
Diesel Supplement for information on checking
your vehicle’s coolant.
The coolant recovery
tank is located near the
center of the engine
compartment. See
Engine Compartment
Overview on page 296
for more information
on location.
The vehicle must be on a level surface. When
your engine is cold, the coolant level should be at
the COLD FILL mark, or a little higher.
Adding Coolant
If you need more coolant, add the proper
DEX-COOL®coolant mixture at the coolant
recovery tank, but be careful not to spill it.
{CAUTION:
Turning the radiator pressure cap when
the engine and radiator are hot can allow
steam and scalding liquids to blow out
and burn you badly. With the coolant
recovery tank, you will almost never
have to add coolant at the radiator. Never
turn the radiator pressure cap — even
a little — when the engine and radiator
are hot.
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{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.
Occasionally check the coolant level in the
radiator. For information on how to add coolant to
the radiator, seeCooling System on page 311.
Radiator Pressure Cap
The radiator pressure cap is located near the
center of the engine compartment. SeeEngine
Compartment Overview on page 296for more
information on location.
Notice:If the pressure cap is not tightly
installed, coolant loss and possible engine
damage may occur. Be sure the cap is properly
and tightly secured.
Engine Overheating
You will find an engine coolant temperature gage
on your vehicle’s instrument panel. SeeEngine
Coolant Temperature Gage on page 178for more
information.
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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.
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.
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. See “Driving on Grades” under
Towing a Trailer on page 266.
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.
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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, 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.Cooling System
If your vehicle has a diesel engine, see “Van
Models” under “Cooling System” in the
DURAMAX
®Diesel Supplement.
When you decide it is safe to lift the hood, here is
what you will see:
A. Radiator Pressure Cap
B. Coolant Recovery Tank
C. Engine Cooling Fan(s)
If the coolant inside the coolant recovery tank is
boiling, do not do anything else until it cools down.
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When the engine is cold, the coolant level should
be at or above the COLD FILL 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, fuel operated heater (FOH),
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. See if the engine cooling fan speed
increases 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.
How to Add Coolant to the Coolant
Recovery Tank for Gasoline Engines
If your vehicle has a diesel engine, see “How
to Add Coolant to the Coolant Recovery Tank”
under “Van Models” in the Cooling System section
of the DURAMAX
®Diesel Supplement for the
proper coolant fill procedure.
If you have not found a problem yet, but the
coolant level is not at the COLD FILL mark, add a
50/50 mixture of clean, drinkable water and
DEX-COOL
®engine coolant at the coolant
recovery tank. SeeEngine Coolant on page 306
for more information.
312