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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 the engine
without coolant is not covered by the 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 the warranty. Always
use DEX-COOL
®(silicate-free) coolant in the 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 5-24for more information.
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{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 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 the washer uid tank only three-quarters full
when it is very cold. This allows for uid
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 the vehicle’s
windshield washer system and paint.
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
components in the engine compartment.
Coolant contains ethylene glycol, and it will
burn if the engine parts are hot enough. Do not
spill coolant on a hot engine or components in
the engine compartment.
When the coolant in the coolant recovery tank is at the
COLD FILL mark, start your vehicle.
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If the overheat warning continues, there is one more
thing you can try. You can add the proper coolant
mixture directly to the radiator, but be sure the cooling
system is cool before you do it.
{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.
How to Add Coolant to the Radiator for
Gasoline Engines
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.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.
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3. Fill the radiator with the proper DEX-COOL®
coolant mixture, up to the base of the filler
neck. SeeEngine Coolant on page 5-24for more
information about the proper coolant mixture.4. Then fill the coolant recovery tank to the COLD
FILL mark.
5. Put the cap back on the coolant recovery tank, but
leave the radiator pressure cap off.
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6. Start the engine and let it run until you can feel the
upper radiator hose getting hot. Watch out for the
engine cooling fan.
7. By this time, the coolant level inside the radiator
filler neck may be lower. If the level is lower, add
more of the proper DEX-COOL
®coolant mixture
through the filler neck until the level reaches
the base of the filler neck.
8. Then replace the pressure cap. At any time during
this procedure if coolant begins to flow out of the
filler neck, reinstall the pressure cap.
Engine Fan Noise
Your vehicle has a clutched engine cooling fan. When
the clutch is engaged, the fan spins faster to provide
more air to cool the engine. In most everyday driving
conditions, the fan is spinning slower and the clutch is
not fully engaged. This improves fuel economy and
reduces fan noise. Under heavy vehicle loading, trailer
towing, and/or high outside temperatures, the fan
speed increases as the clutch more fully engages, so
you may hear an increase in fan noise. This is
normal and should not be mistaken as the transmission
slipping or making extra shifts. It is merely the cooling
system functioning properly. The fan will slow down
when additional cooling is not required and the clutch
partially disengages.
You may also hear this fan noise when you start the
engine. It will go away as the fan clutch partially
disengages.
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Windshield Washer Fluid
What to Use
When you need windshield washer fluid, be sure to read
the manufacturer’s instructions before use. If you will
be operating your vehicle in an area where the
temperature may fall below freezing, use a fluid that has
sufficient protection against freezing.
Adding Washer Fluid
Open the cap with the
washer symbol on it. Add
washer fluid until the
tank is full. SeeEngine
Compartment Overview on
page 5-14for reservoir
location.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 the washer uid tank only three-quarters full
when it is very cold. This allows for uid
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 the vehicle’s
windshield washer system and paint.
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(D) Construction Code:A letter code is used to
indicate the type of ply construction in the tire.
The letter R means radial ply construction;
the letter D means diagonal or bias ply
construction; and the letter B means belted-bias
ply construction.
(E) Rim Diameter
:Diameter of the wheel in
inches.
(F) Service Description
:The service description
indicates the load range and speed rating of a
tire. The load index can range from 1 to 279.
Speed ratings range from A to Z.
Tire Terminology and De nitions
Air Pressure:The amount of air inside the
tire pressing outward on each square inch of the
tire. Air pressure is expressed in pounds per
square inch (psi) or kilopascal (kPa).
Accessory Weight
:This means the combined
weight of optional accessories. Some examples of
optional accessories are, automatic transmission,
power steering, power brakes, power windows,
power seats, and air conditioning.Aspect Ratio
:The relationship of a tire’s height
to its width.
Belt
:A rubber coated layer of cords that is
located between the plies and the tread. Cords
may be made from steel or other reinforcing
materials.
Bead
:The tire bead contains steel wires wrapped
by steel cords that hold the tire onto the rim.
Bias Ply Tire
:A pneumatic tire in which the plies
are laid at alternate angles less than 90 degrees
to the centerline of the tread.
Cold Tire Pressure
:The amount of air pressure
in a tire, measured in pounds per square inch
(psi) or kilopascals (kPa) before a tire has built up
heat from driving. SeeInflation - Tire Pressure
on page 5-64.
Curb Weight
:The weight of a motor vehicle with
standard and optional equipment including the
maximum capacity of fuel, oil, and coolant,
but without passengers and cargo.
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Scheduled Maintenance
Service MaintenanceIMaintenanceII
Change engine oil and filter. SeeEngine Oil (Gasoline Engine) on page 5-15.
Reset oil life system. SeeEngine Oil Life System on page 5-18.An Emission
Control Service.••
Lubricate chassis components.See footnote #.••
Visually check for any leaks or damage.See footnote (j).••
Inspect engine air cleaner filter. If necessary, replace filter. SeeEngine Air
Cleaner/Filter on page 5-20.See footnote (l).•
Rotate tires and check inflation pressures and wear. SeeTire Inspection and
Rotation on page 5-71and “Tire Wear Inspection” inAt Least Once a Month
on page 6-10.••
Inspect brake system.See footnote (a).••
Check engine coolant and windshield washer fluid levels and add fluid as
needed.••
Perform any needed additional services. See “Additional Required Services”
in this section.••
Inspect suspension and steering components.See footnote (b).•
Inspect engine cooling system.See footnote (c).•
Inspect wiper blades.See footnote (d).•
Inspect restraint system components.See footnote (e).•
6-5