Engine Coolant Temperature Gage
This gage shows the engine coolant temperature.
If the gage pointer moves into the red area your engine
is too hot!
It means that your engine coolant has overheated. If you
have been operating your vehicle under normal operating
conditions, you should pull off the road, stop your vehicle,
and turn off the engine as soon as possible.
SeeEngine Overheating on page 5-25.
Malfunction Indicator Lamp
Check Engine Light
Your vehicle has a
computer which monitors
operation of the fuel,
ignition, and emission
control systems.
This system is called OBD II (On-Board
Diagnostics-Second Generation) and is intended to
assure that emissions are at acceptable levels for the
life of the vehicle, helping to produce a cleaner
environment. The Check Engine light comes on to
indicate that there is a problem and service is required.
Malfunctions often will be indicated by the system
before any problem is apparent. This may prevent more
serious damage to your vehicle. This system is also
designed to assist your service technician in correctly
diagnosing any malfunction.
Notice:If you keep driving your vehicle with this
light on, after awhile, your emission controls
may not work as well, your fuel economy may not
be as good, and your engine may not run as
smoothly. This could lead to costly repairs that
may not be covered by your warranty. United States
Canada
3-36
Making Turns
Notice:Making very sharp turns while trailering
could cause the trailer to come in contact with the
vehicle. Your vehicle could be damaged. Avoid
making very sharp turns while trailering.
When you’re turning with a trailer, make wider turns
than normal. Do this so your trailer won’t strike soft
shoulders, curbs, road signs, trees or other objects.
Avoid jerky or sudden maneuvers. Signal well in
advance.
Turn Signals When Towing a Trailer
When you tow a trailer, your vehicle has to have extra
wiring and a heavy-duty turn signal flasher (included
in the optional trailering package).
The arrows on your instrument panel will flash whenever
you signal a turn or lane change. Properly hooked up,
the trailer lamps will also flash, telling other drivers
you’re about to turn, change lanes or stop.
When towing a trailer, the arrows on your instrument
panel will flash for turns even if the bulbs on the trailer
are burned out. Thus, you may think drivers behind
you are seeing your signal when they are not. It’s
important to check occasionally to be sure the trailer
bulbs are still working.
Driving On Grades
Reduce speed and shift to a lower gearbeforeyou start
down a long or steep downgrade. If you don’t shift
down, you might have to use your brakes so much that
they would get hot and no longer work well.
You can tow in DRIVE (D). You may want to shift the
transmission to THIRD (3) or a lower gear under heavy
loads and/or hilly conditions.
When towing at high altitude on steep uphill grades,
consider the following: Engine coolant will boil at a lower
temperature than at normal altitudes. If you turn your
engine off immediately after towing at high altitude
on steep uphill grades, your vehicle may show signs
similar to engine overheating. To avoid this, let the
engine run while parked (preferably on level ground)
with the automatic transmission in PARK (P) for a
few minutes before turning the engine off. If you do
get the overheat warning, seeEngine Overheating
on page 5-25.
4-50
A. Battery. SeeBattery on page 5-38.
B. Radiator Pressure Cap. SeeRadiator Pressure Cap
on page 5-25.
C. Coolant Recovery Tank. SeeCooling System on
page 5-26.
D. Automatic Transmission Fluid Dipstick. See
“Checking the Fluid Level” underAutomatic
Transmission Fluid on page 5-19.
E. Engine Oil Fill Cap. See “When to Add Engine Oil”
underEngine Oil (Gasoline Engine) on page 5-13.
F. Engine Oil Dipstick. See “Checking Engine Oil” under
Engine Oil (Gasoline Engine) on page 5-13.
G. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 5-18.
H. Power Steering Fluid Reservoir. SeePower Steering
Fluid on page 5-32.
I. Brake Master Cylinder Reservoir. See “Brake Fluid”
underBrakes on page 5-34.
J. Windshield Washer Fluid Reservoir. See “Adding
Washer Fluid” underWindshield Washer Fluid
on page 5-33.Engine Oil (Gasoline Engine)
If your vehicle has a diesel engine, see “Engine Oil” in
the DURAMAX®Diesel Engine Supplement.
Checking Engine Oil
It is a good idea to check your engine oil every time you
get fuel. In order to get an accurate reading, the oil
must be warm and the vehicle must be on level ground.
The engine oil dipstick handle is a yellow loop.
SeeEngine Compartment Overview on page 5-12
for the location of the engine oil dipstick.
1. Turn off the engine and give the oil several minutes
to drain back into the oil pan. If you do not do this,
the oil dipstick might not show the actual level.
2. Pull out the dipstick and clean it with a paper towel
or cloth, then push it back in all the way. Remove it
again, keeping the tip down, and check the level.
5-13
How to Add Automatic
Transmission Fluid
Refer to the Maintenance Schedule to determine what
kind of transmission fluid to use. SeeRecommended
Fluids and Lubricants (Gasoline Engine) 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 your vehicle, and the damages
may not be covered by your warranty. Always
use the automatic transmission uid listed in
Recommended Fluids and Lubricants (Gasoline
Engine) 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.
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 5-25.
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.
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.
5-22
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.
SeeEngine Compartment
Overview on page 5-12for
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.
{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.
5-24
Occasionally check the coolant level in the radiator.
For information on how to add coolant to the radiator,
seeCooling System on page 5-26.
Radiator Pressure Cap
The radiator pressure cap is located near the center of
the engine compartment. SeeEngine Compartment
Overview on page 5-12for 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 3-36for more information.
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.
5-25
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.
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 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.
5-27
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 5-22for 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.
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
DEX-COOL
®coolant.
Notice:
When using concentrated washer uid, follow the
manufacturer’s instructions for adding water.
Do not mix water with ready-to-use washer uid.
Water can cause the solution to freeze and
damage your washer uid tank and other parts of
the washer system. Also, water does not clean as
well as washer uid.
Fill your washer uid tank only three-quarters full
when it is very cold. This allows for expansion if
freezing occurs, which could damage the tank if
it is completely full.
Do not use engine coolant (antifreeze) in your
windshield washer. It can damage your washer
system and paint.
5-28