recommended oil 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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Diesel Fuel Requirements and
Fuel System
Some states and provinces have restrictions on the
purchase of diesel fuel for light-duty vehicles and require
you to buy permits or pay special taxes. Some of these
restrictions apply only to residents, and others apply
to both residents and visitors. These restrictions can
change. To learn the current restrictions in any state
or province, contact your auto club, the police or other
officials.
Diesel Engine Fuel
Notice:Diesel fuel or fuel additives not
recommended in this manual could damage your
fuel system, fuel-operated heater (FOH) (Van models
only) and engine. Your warranty would not cover
this damage. And:
Diesel fuel that has been mixed with engine oil
or automatic transmission uid could damage
your engine and emission controls.
Aftermarket diesel fuel additives are not tested
by General Motors. Some additives, particularly
those which contain alcohol or water emulsiers,
may damage your fuel system. If you believe that
unique circumstances call for a fuel additive to
be used, consult your dealer for advice.
If you ever run out of diesel fuel, it can be difficult
to restart your engine. To avoid all this, never let
your tank get empty.
If gasoline is ever accidentally added to the fuel
tank, to avoid severe engine damage, do not run
the engine until the fuel tank can be drained.
If you run out of fuel,Running Out of Fuel on page 5-11
tells you how to restart your engine.
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What Fuel to Use
In the United States, for best results use No. 2-D diesel
fuel year-round (above and below freezing conditions)
as oil companies blend No. 2-D fuel to address climate
differences. No. 1-D diesel fuel may be used in very
cold temperatures (when it stays below 0°F or−18°C);
however, it will produce a power and fuel economy loss.
Avoid the use of No. 1-D diesel fuel in warm or hot
climates. It may result in stalling, poor starting when the
engine is hot, and may damage the fuel injection system.
At a minimum, the diesel fuel you use should meet the
latest version of ASTM specification D 975 (Grade Low
Sulfur) in the United States. In addition, the Engine
Manufacturers Association (EMA) has identified
properties of an improved diesel fuel for better engine
performance and durability. Diesel fuels corresponding to
the EMA Recommended Guideline on Premium Diesel
Fuel (FQP-1A) could provide better starting, less noise,
and better vehicle performance. If there are questions
about the fuel you are using, contact your fuel supplier.It is acceptable to use diesel fuel containing up to 5%
biodiesel (B5), but the final blended fuel must meet the
same specification, ASTM D 975 (Grade Low Sulfur),
as other fuels used in your vehicle, and the biodiesel
used for making this fuel must meet the latest version of
ASTM specification D 6751. Biodiesel is produced from
vegetable oils or animal fat that have been chemically
modified to reduce the possibility of damage to your fuel
system and engine. Higher concentration (i.e., greater
than B5) biodiesel-containing fuels or the use of
unmodified bio-oils blended into diesel fuel at any
concentration is not recommended and could damage
your fuel system and engine. Such damage would not be
covered by your warranty. If there are questions about
the biodiesel-containing fuels you are using, contact your
fuel supplier.
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It is acceptable to use diesel fuel containing up to 5%
biodiesel (B5), but the final blended fuel must meet the
same specification, CAN/CGSB-3.517 (Low Sulfur
Diesel) in Canada, as other fuels used in your vehicle,
and the biodiesel used for making this fuel must meet the
latest version of ASTM specification D 6751. Biodiesel is
produced from vegetable oils or animal fat that have been
chemically modified to reduce the possibility of damage
to your fuel system and engine. Higher concentration
(i.e., greater than B5) biodiesel-containing fuels or the
use of unmodified bio-oils blended into diesel fuel at any
concentration is not recommended and could damage
your fuel system and engine. Such damage would not be
covered by your warranty. If there are questions about
the biodiesel-containing fuels you are using, contact your
fuel supplier.
Very Cold Weather Operation
Follow the instructions listed previously under the
heading “What Fuel to Use.”
Notice:Never use home heating oil or gasoline in
your diesel engine. They can cause engine damage.
In cold weather, your fuel filter may become clogged
(waxed). To unclog it, move the vehicle to a warm garage
area and warm the filter to between 32°F and 50°F
(0°C to 10°C). You will not need to replace it. Additional
information on the fuel filter follows.
Water in Fuel
{CAUTION:
Diesel fuel containing water is still ammable.
You could be burned. If you ever try to drain
water from your fuel, keep sparks, ames and
smoking materials away from the mixture.
Notice:If there is water in your diesel fuel and the
weather is warm or humid, fungus and bacteria can
grow in the fuel. They can damage your fuel system
and fuel operated heater (FOH) (if equipped). A diesel
fuel biocide can be used to sterilize your fuel system.
However, your fuel system may still need to be
cleaned. Your dealer can advise you of the
appropriate solution.
If your fuel tank needs to be purged to remove
water, see your dealer or a qualied technician.
Improper purging can damage your fuel system
and block your FOH.
Sometimes, water can be pumped into your fuel tank
along with your diesel fuel. This can happen if a service
station doesn’t regularly inspect and clean its fuel tanks,
or if it gets contaminated fuel from its suppliers.
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SeeEngine Compartment
Overview on page 5-18for
the location of the engine
oil fill cap.
Be sure to add enough oil to put the level somewhere
in the proper operating range. Push the dipstick all the
way back in when you are through.What Kind of Engine Oil to Use
Look for these two things:
•CI-4 or CH-4
Oils designated as API CI-4 or CH-4 are
recommended for your vehicle. The CI-4 or CH-4
designations may appear either alone, together, or
in combination with other API designations, such
as API CI-4/SL.
These letters show American Petroleum
Institute (API) levels of quality.
Notice:Use only engine oils that have one of these
designations CI-4 or CH-4 for the DURAMAX
®diesel
engine. Failure to use the recommended oils can
result in engine damage not covered by your
warranty.
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•SAE 15W-40
As shown in the viscosity chart, SAE 15W-40 is
best for your vehicle. However, you can use
SAE 10W-30 at temperatures above 0°F (−18°C).
When it is very cold, below 0°F (−18°C), you should
use SAE 5W-40 to improve cold starting. 5W-40
is not recommended for use at high temperatures,
above 100°F (38°C).
These numbers on the oil container show its
viscosity, or thickness. Do not use other viscosity
oils such as SAE 10W-40 or SAE 20W-50.
This doughnut-shaped logo
(symbol) is used on most
oil containers to help you
select the correct oil. It
means that the oil has been
certified by the American
Petroleum Institute.
You should look for this on the oil container, and use
onlythose oils that display this logo.
GM Goodwrench
®oil of the recommended viscosity
grades meets all the requirements for your vehicle.
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Engine Oil Additives
Do not add anything to your oil. The recommended oils
with the API service symbol are all you will need for
good performance and engine protection.
Engine Oil Life System
When to Change Engine Oil
Your vehicle has a computer system that lets you know
when to change the engine oil and filter. This is based on
engine timing, engine load, and engine temperature, and
not on mileage. Based on driving conditions, the mileage
at which an engine oil change will be indicated can vary
considerably. For the oil life system to work properly, you
must reset the system every time the oil is changed.
When the system has calculated that oil life has been
diminished, it will indicate that an oil change is necessary.
A CHANGE ENGINE OIL message in pickup models
or a change engine oil light in van models will come on.
Change your oil as soon as possible within the next
600 miles (1 000 km). It is possible that, if you are driving
under the best conditions, the oil life system may not
indicate that an oil change is necessary for over a year.
However, your engine oil and filter must be changed at
least once a year and at this time the system must be
reset. Your dealer has GM-trained service people who
will perform this work using genuine GM parts and reset
the system. It is also important to check your oil regularly
and keep it at the proper level.If the system is ever reset accidentally, you must
change your oil at 3,000 miles (5 000 km) since your
last oil change. Remember to reset the oil life system
whenever the oil is changed.
How to Reset the Engine Oil Life
System
The Engine Oil Life System calculates when to change
your engine oil and filter based on vehicle use. Anytime
your oil is changed, reset the system so it can calculate
when the next oil change is required. If a situation occurs
where you change your oil prior to a CHANGE ENGINE
OIL message (pickup models) or a change engine oil light
(van models) being turned on, reset the system.
To reset the Engine Oil Life System, do the following:
1. Turn the ignition key to RUN with the engine off.
2. Fully press and release the accelerator pedal
three times within five seconds.
Pickup Models: If the OIL LIFE RESET message
flashes for 10 seconds, the system is resetting.
Van Models: If the change engine oil light flashes
for five seconds, the system is reset.
3. Turn the key to LOCK.
If the message or light comes back on when you start
your vehicle, the engine oil life system has not reset.
Repeat the procedure. If it still does not reset, see your
dealer for service.
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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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