coolant temperature CHEVROLET DURAMAX 2006 Owners Manual

When your engine is cold, let it run for a few minutes
before you move your vehicle. This lets oil pressure
build up. Your engine will sound louder when it’s cold.
Notice:If you are not in an idling vehicle and the
engine overheats, you would not be there to see the
overheated engine indication. This could damage
your vehicle. Do not let your engine run when you are
not in your vehicle.
Cold Weather Starting (Diesel Engine)
The following tips will help you get good starting in
cold weather.
Use the recommended engine oil when the outside
temperature drops below freezing. SeeEngine Oil on
page 5-21. When the outside temperature drops below
0° F (–18°C), use of the engine coolant heater is
recommended.
If you experience longer cranking times, notice an
unusual amount of exhaust smoke or are at higher
altitudes (over 7,000 ft. or 2 135 m), you may use your
engine coolant heater. SeeEngine Coolant Heater
on page 2-8.
SeeDiesel Fuel Requirements and Fuel System on
page 5-2for information on what fuel to use in cold
weather.
If Your Diesel Engine Won’t Start
If you’ve run out of fuel, look atRunning Out of Fuel
on page 5-11. SeeDiesel Fuel Requirements and Fuel
System on page 5-2.
If you’re not out of fuel, and your engine won’t start,
do this:
Turn your ignition key to RUN. Immediately after the wait
to start light goes off, turn the ignition key to START.
If the light doesn’t go off, wait a few seconds, then try
starting your engine again. See your dealer as soon
as you can for a starting system check.
If the light comes on and then goes off and you know your
batteries are charged, but your engine still won’t start,
your vehicle needs service.
If the light does not come on when the engine is cold,
your vehicle needs service.
If your batteries don’t have enough charge to start your
engine, see “Battery” in the owner’s manual Index.
Be sure you have the right oil for your engine, and that
you’ve changed the oil at the proper times. If you use
the wrong oil, your engine may be harder to start.
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Be sure you are using the proper fuel for existing
weather conditions. SeeDiesel Fuel Requirements
and Fuel System on page 5-2.
If the engine starts, runs a short time, then stops, your
vehicle needs service.
{CAUTION:
Do not use gasoline or starting aids, such as
ether, in the air intake. They could damage
your engine. There could also be a re, which
could cause serious personal injury.
Elevated Idle/Exhaust Restrictor
The engine has a cold temperature high idle and exhaust
restrictor feature which elevates the engines idle speed
from 680 to 1200 rpms, and restricts the exhaust gas
flow, when outside temperatures are below 32°F (0°C),
and the engine coolant temperature is below 150°F
(65°C.) This feature enhances heater performance
by raising the engine coolant temperature faster.For pickup models, this feature can be turned off and
on using the DIC steering wheel control buttons. If your
vehicle is not equipped with the DIC steering wheel
control buttons, do the following to turn on this feature:
1. Turn the ignition to RUN, with the vehicle off.
2. Press the accelerator pedal to the floor and hold
while quickly pressing the brake pedal three times
in less than eight seconds.
3. Release the accelerator pedal and start the engine.
When the engine is started, it will slowly ramp up to the
high idle speed after a delay of a few seconds up to
approximately two minutes. For this method to work
properly there must be no throttle or brake pedal faults.
The engine idle speed will return to normal once the
following conditions are met:•Once engine coolant temperature reaches
150°F (65°C).
•Air intake temperature reaches 32°F (0°C).
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The high idle speed will be temporarily interrupted
and the engine speed will return to normal if any of
the following conditions occur:
•The brake pedal is applied.
•The accelerator pedal is pressed.
•The automatic transmission is shifted out of
PARK (P) or NEUTRAL (N).
•The clutch pedal on the manual transmission is
pressed (pickup models).
•Vehicle speed is detected.
Once these inputs are removed, the engine idle speed
will slowly ramp back up to high idle after the normal
delay, if the conditions for engine coolant temperature
and air intake temperature are still met.
Manual High Idle System
(Van Models Only)
If your vehicle has this
feature, the manual high
idle switch is located
on the instrument panel.
This system can be used to increase your engine idle
speed whenever the following conditions are met:
•The brake pedal is not pressed.
•The vehicle speed is below about 5 mph (8 km/h).
•The transmission is in NEUTRAL (N) or PARK (P).
The manual high idle feature is activated by pressing
the switch on the instrument panel. When the switch is
pressed again, or any of the previous conditions are not
met, manual high idle will be deactivated. The manual
high idle has been preset at the factory. Your dealer may
change the setting to fit your needs.
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Fuel Operated Heater (FOH)
(Van Models Only)
If your vehicle includes a fuel operated heater (FOH),
it will enhance heater performance and will reduce the
amount of time it takes to warm the inside of your vehicle
in cold conditions below 40°F (4.4°C). The fuel operated
heater is installed in the frame rail on the driver’s side of
the vehicle and uses diesel to warm up the engine
coolant, which finally warms up the passenger’s cabin
air. The FOH works automatically, depending on the
fuel level, engine coolant temperature and outside air
temperature. It works only with the engine running.
Engine Coolant Heater
In very cold weather, 0°F (−18°C) or colder, the engine
coolant heater can help. You’ll get easier starting
and better fuel economy during engine warm-up.
Usually, the coolant heater should be plugged in a
minimum of four hours prior to starting your vehicle.
To Use the Engine Coolant Heater
1. Turn off the engine.
2. Open the hood and unwrap the electrical cord.
The cord is located in the engine compartment,
on the passenger’s side of the vehicle, near the
right side engine mount.
3. Plug it into a normal, grounded 110-volt AC outlet.
{CAUTION:
Plugging the cord into an ungrounded outlet
could cause an electrical shock. Also, the
wrong kind of extension cord could overheat
and cause a re. You could be seriously injured.
Plug the cord into a properly grounded
three-prong 110-volt AC outlet. If the cord
will not reach, use a heavy-duty three-prong
extension cord rated for at least 15 amps.
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4. Before starting the engine, be sure to unplug and
store the cord as it was before to keep it away
from moving engine parts. If you don’t, it could
be damaged.
How long should you keep the coolant heater plugged in?
The answer depends on the outside temperature. You
may wish to use your coolant heater to improve ease
of starting at temperatures between 0°F (−18°C)
and−20°F (−29°C).Keep the coolant heater plugged in for
a minimum of four hours. At temperatures below−20°F
(−29°C), the coolant heater should remain plugged in for
at least eight hours. It will not harm either the coolant
heater or the vehicle to leave the coolant heater plugged
in longer than the times stated. Be sure to remove and
store the cord before starting the engine. SeeDiesel
Fuel Requirements and Fuel System on page 5-2for
information on what fuel to use in cold weather.
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Towing
Towing a Trailer
When towing at high altitude on steep uphill grades,
consider the following:
Engine coolant will boil at a lower temperature than sea
level. 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 automatic transmission equipped
vehicles in PARK (P) or manual transmission equipped
vehicles in NEUTRAL with the park brake applied for at
least five minutes before turning the engine off. If you do
get the overheat warning, seeEngine Overheating on
page 5-39.
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A. Battery
B. Coolant Surge Tank
C. Automatic Transmission Dipstick
D. Engine Fan
E. Engine Air Cleaner/Filter
F. Engine Oil Fill Cap
G. Power Steering Fluid Reservoir
H. Brake Fluid Reservoir
I. Windshield Washer Fluid Reservoir
Engine Oil
Checking Engine Oil
It is a good idea to check your engine oil level every
time you get fuel.
The engine oil dipstick handle is a yellow loop.
SeeEngine Compartment Overview on page 5-18
for the location of the engine oil dipstick.In order to get an accurate reading, the oil must be
warm, at normal operating temperature, and the vehicle
must be on level ground.
1. Turn off the engine and give the oil at least
five minutes to drain back into the oil pan. With a
cool engine, allow 30 minutes. 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 a cloth, then push it back in all the way. Remove
it again, keeping the tip down.
When to Add Engine Oil
If the oil is below the cross-hatched area at the tip of the
dipstick, you will need to add at least two quarts/liters of
oil. But you must use the right kind. This section explains
what kind of oil to use. For engine oil crankcase capacity,
seeSpecication Charts on page 5-50.
Notice:Do not add too much oil. If the engine
has so much oil that the oil level gets above the
cross-hatched area that shows the proper operating
range, the engine could be damaged.
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How to Add Fluid
Refer to the Maintenance Schedule to determine what
kind of transmission fluid to use. SeeRecommended
Fluids and Lubricants on page 6-15.
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 (0.5L). 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 on page 6-15.
•After adding fluid, recheck the fluid level as
described under “How to Check” 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
Pickup Models
The cooling system in your vehicle is filled with
DEX-COOL®engine coolant. This coolant is designed
to remain in your vehicle for 5 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 5-39.
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, or radiator
corrosion. In addition, the engine coolant may
require changing sooner, at the rst maintenance
service after each 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.
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Van Models
The cooling system in your vehicle is filled with
DEX-COOL®engine coolant. This coolant is designed to
remain in your vehicle for 5 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 5-39.
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.
What to Use
Use a mixture of one-halfclean, drinkable waterand
one-half DEX-COOL®coolant which won’t damage
aluminum parts. If you use this coolant mixture,
you don’t 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. 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: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.
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Adding Coolant
If you need more coolant, add the proper DEX-COOL®
coolant mixtureat the coolant recovery tank, but be
careful not to spill it.
{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 replacing the pressure cap, make sure it is
hand-tight.
Radiator Pressure Cap
The radiator pressure cap must be tightly installed.
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.
Coolant Surge Tank Pressure Cap
The surge tank pressure
cap must be tightly
installed.
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 the
instrument panel cluster. For pickup models, the ENGINE
OVERHEATED message may appear in the Driver
Information Center (DIC). See your owner’s manual for
more information.
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