engine overheat 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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Winter Cover (Pickup Models Only)
If your vehicle includes a winter cover, it will enhance
heater performance and will reduce the amount of time it
takes to warm the inside of your vehicle in extremely cold
conditions (below 0°F (−18°C)). The winter cover consists
of two parts, the front bumper cover (if equipped) and
the grille cover. The winter cover installs over the front
bumper of your vehicle and restricts the air flowing to
the engine compartment by covering the radiator grille.
Usage Guidelines
The winter cover should only be used while operating
your vehicle in extremely cold temperatures. In these
temperatures, the vehicle does not need a large amount
of air to properly cool the engine. During periods of
operation when more airflow is required to cool the
vehicle, the winter cover should not be used. The
following usage guidelines will allow adequate airflow
for proper radiator grille and air cooler performance:
•Do not use the winter cover when temperatures are
expected to be above 32°F (0°C). Use of the cover
in these conditions could cause your vehicle to
overheat. If this happens while the cover is being
used, remove the cover.
•Do not use the winter cover if towing a trailer. The
added power needed to tow a trailer requires the
radiator grille to have full airflow under all conditions.
Your vehicle may overheat if the cover is used while
towing a trailer.
•Do not modify the cover. The winter cover does
not cover some sections of the front of the vehicle
because these openings are needed to provide
enough airflow to the radiator grille and air cooler
in extremely cold temperatures.
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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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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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Diesel Fuel Requirements and Fuel System.......5-2
Diesel Engine Fuel.........................................5-2
What Fuel to Use...........................................5-3
Very Cold Weather Operation...........................5-5
Water in Fuel.................................................5-5
Water in Fuel Light Chart................................5-6
Running Out of Fuel.....................................5-11
Fuel Filter Replacement.................................5-12
Filling the Tank............................................5-15
Filling a Portable Fuel Container.....................5-17Checking Things Under the Hood....................5-18
Engine Compartment Overview.......................5-18
Engine Oil...................................................5-21
Engine Oil Life System..................................5-24
Engine Air Cleaner/Filter................................5-25
Automatic Transmission Fluid.........................5-29
Engine Coolant.............................................5-34
Radiator Pressure Cap..................................5-39
Coolant Surge Tank Pressure Cap..................5-39
Engine Overheating.......................................5-39
Cooling System............................................5-41
Capacities and Specications..........................5-50
Specification Charts......................................5-50
Section 5 Service and Appearance Care
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Automatic Transmission Fluid
When to Check and Change
(Pickup Models)
A good time to check your automatic transmission fluid
level is when the engine oil is changed.
Change both the fluid and filter every 25,000 miles
(41 500 km) if the vehicle is mainly driven under one
or more of these conditions:
•In heavy city traffic where the outside temperature
regularly reaches 90°F (32°C) or higher.
•In hilly or mountainous terrain.
•When doing frequent trailer towing.
•Uses such as found in taxi, police or
delivery service.
If you do not use your vehicle under any of
these conditions, change the fluid and filter
every 50,000 miles (83 000 km).
SeeScheduled Maintenance on page 6-4.
How to Check
Because this operation can be a little difficult, you may
choose to have this done at the dealership 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 part 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.
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When to Check and Change
(Van Models)
A good time to check your automatic transmission fluid
level is when the engine oil is changed.
Change the fluid and filter at the intervals listed in
“Additional Required Services”. SeeAdditional
Required Services on page 6-7.
And be sure to use the transmission fluid listed
in “Recommended Fluids and Lubricants”. See
Recommended Fluids and Lubricants on page 6-15
for more information.
How to Check
Because this operation can be a little difficult, you may
choose to have this done at the dealership 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 part 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 until the engine temperature gage moves and
then remains steady for 10 minutes.
A cold 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.
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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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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.
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. SeeRecommended Fluids and Lubricants
on page 6-15for more information.
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Checking Coolant
The coolant surge tank
is located in the engine
compartment on the
passenger’s side of the
vehicle. SeeEngine
Compartment Overview
on page 5-18for more
information on its location.
{CAUTION:
Turning the surge tank pressure cap when the
engine and radiator are hot can allow steam
and scalding liquids to blow out and burn you
badly. Never turn the surge tank pressure
cap — even a little — when the engine and
radiator are hot.The vehicle must be on a level surface. When your
engine is cold, the coolant level should be at the
FULL COLD mark.
Adding Coolant
If you need more coolant, add the proper DEX-COOL®
coolant mixtureat the surge tank, but only when the
engine is cool. If the surge tank is empty, seeEngine
Overheating on page 5-39.
{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.
When replacing the pressure cap, make sure it is
hand- tight.
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