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How to Check Automatic Transmission
Fluid
Because this operation can be a little difficult, you may
choose to have this done at the dealer/retailer service
department.
If you do it yourself, be sure to follow all the instructions
here, or you could get a false reading on the dipstick.
Notice:Too much or too little uid can damage
your transmission. Too much can mean that some
of the uid could come out and fall on hot engine
parts or exhaust system parts, starting a re.
Too little uid could cause the transmission to
overheat. Be sure to get an accurate reading if
you check your transmission uid.
Wait at least 30 minutes before checking the
transmission fluid level if you have been driving:
•When outside temperatures are above 90°F (32°C).
•At high speed for quite a while.
•In heavy traffic — especially in hot weather.
•While pulling a trailer.
To get the right reading, the fluid should be at normal
operating temperature, which is 180°F to 200°F
(82°C to 93°C).Get the vehicle warmed up by driving about
15 miles (24 km) when outside temperatures are above
50°F (10°C). If it is colder than 50°F (10°C), drive the
vehicle in D (DRIVE) until the engine temperature gage
moves and then remains steady for 10 minutes.
A cold fluid check can be made after the vehicle has
been sitting for eight hours or more with the engine off,
but this is used only as a reference. Let the engine run
at idle for five minutes if outside temperatures are 50°F
(10°C) or more. If it is colder than 50°F (10°C), you may
have to idle the engine longer. Should the fluid level be
low during this cold check, you must check the fluid hot
before adding fluid. Checking the fluid hot will give you a
more accurate reading of the fluid level.
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 P (PARK).
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 P (PARK).
4. Let the engine run at idle for three minutes or more.
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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 5-14for
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. SeeRecommended
Fluids and Lubricants on page 6-13.
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 the vehicle, and the damages
may not be covered by the vehicle’s warranty.
Always use the automatic transmission uid listed in
Recommended Fluids and Lubricants on page 6-13.
•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.
Cooling System
If your vehicle has a diesel engine, see “Van Models”
under “Cooling System” in the DURAMAX®Diesel
Supplement.
The Cooling System allows the engine to maintain the
correct working temperature.
A. Radiator Pressure Cap
B. Coolant Recovery Tank
C. Engine Cooling Fan(s)
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{CAUTION:
An electric engine cooling fan under the hood can
start up even when the engine is not running and
can cause injury. Keep hands, clothing, and tools
away from any underhood electric fan.
{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 fire, and you could be burned.
Get any leak fixed before you drive the vehicle.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.
Engine Coolant
The cooling system in the vehicle is filled with
DEX-COOL®engine coolant. This coolant is
designed to remain in the vehicle for five years or
150,000 miles (240 000 km), whichever occurs first.
The following explains the cooling system and how
to check and add coolant when it is low. If there
is a problem with engine overheating, seeEngine
Overheating on page 5-31.
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What to Use
{CAUTION:
Adding only plain water to the cooling system can
be dangerous. Plain water, or some other liquid
such as alcohol, can boil before the proper coolant
mixture will. The vehicle’s coolant warning system
is set for the proper coolant mixture. With plain
water or the wrong mixture, the engine could get
too hot but you would not get the overheat
warning. The engine could catch fire and you or
others could be burned. Use a 50/50 mixture of
clean, drinkable water and DEX-COOL
®coolant.Use a 50/50 mixture of clean, drinkable water and
DEX-COOL
®coolant. If using this mixture, nothing else
needs to be added. This mixture:
•Gives freezing protection down to−34°F (−37°C),
outside temperature.
•Gives boiling protection up to 265°F (129°C),
engine temperature.
•Protects against rust and corrosion.
•Will not damage aluminum parts.
•Helps keep the proper engine temperature.
Notice:If an improper coolant mixture is used,
the engine could overheat and be badly damaged.
The repair cost would not be covered by the vehicle
warranty. Too much water in the mixture can freeze
and crack the engine, radiator, heater core, and other
parts.
Notice:If extra inhibitors and/or additives are used
in the vehicle’s cooling system, the vehicle could
be damaged. Use only the proper mixture of
the engine coolant listed in this manual for the
cooling system. SeeRecommended Fluids and
Lubricants on page 6-13for more information.
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Checking Coolant
The vehicle must be on a level surface when checking
the coolant level.
Check to see if coolant is visible in the coolant recovery
tank. If the coolant inside the coolant recovery tank is
boiling, do not do anything else until it cools down.
If coolant is visible but the coolant level is not at
or above the COLD FILL mark, add a 50/50 mixture
of clean, drinkable water and DEX-COOL
®coolant at the
coolant recovery tank, but be sure the cooling system
is cool before this is done. See for more information
When the engine is cold, the coolant level should be at
or above the COLD FILL mark. If it is not, there could
be a leak in the cooling system.
If the coolant is low, add the coolant or take the vehicle
to a dealer/retailer for service.
How to Add Coolant to the 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.
{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.
Notice:This vehicle has a speci c coolant ll
procedure. Failure to follow this procedure could
cause the engine to overheat and be severely
damaged.
If coolant is needed, add the proper DEX-COOL
®
coolant mixture at the coolant recovery tank.
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How to Add Coolant to the Radiator
If your vehicle has a diesel engine, see “How to
Add Coolant to the Radiator” under “Van Models” in
the Cooling System section of the DURAMAX
®Diesel
Supplement for the proper radiator fill procedure.
{CAUTION:
An electric engine cooling fan under the hood can
start up even when the engine is not running and
can cause injury. Keep hands, clothing, and tools
away from any underhood electric fan.
{CAUTION:
Steam and scalding liquids from a hot cooling
system can blow out and burn you badly. They
are under pressure, and if you turn the radiator
pressure cap — even a little — they can come
out at high speed. Never turn the cap when the
cooling system, including the radiator pressure cap,
is hot. Wait for the cooling system and radiator
pressure cap to cool if you ever have to turn the
pressure cap.
If coolant is needed, add the proper mixture directly to
the radiator, but be sure the cooling system is cool
before this is done.
If coolant is needed, add the proper mixture directly to
the radiator, but be sure the cooling system is cool
before this is done.
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1. You can remove the radiator pressure cap when
the cooling system, including the radiator pressure
cap and upper radiator hose, is no longer hot.
Turn the pressure cap slowly counterclockwise until
it first stops. Do not press down while turning the
pressure cap.
If you hear a hiss, wait for that to stop. A hiss
means there is still some pressure left.
2. Then keep turning the pressure cap, but now push
down as you turn it. Remove the pressure cap.3. Fill the radiator with the proper DEX-COOL®
coolant mixture, up to the base of the filler
neck. SeeEngine Coolant on page 5-25for more
information about the proper coolant mixture.
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