CHEVROLET DURAMAX 2006 Workshop Manual

Van Models
The air cleaner/filter
assembly may have an
air cleaner/filter restriction
indicator that lets you
know when the engine air
cleaner/filter is dirty and
needs to be serviced.
The air cleaner/filter restriction indicator is located on
the air cleaner resonator.
When to Inspect
Inspect the air cleaner/filter every 15,000 miles
(25 000 km) and replace the filter if necessary.
How to Inspect
When the restriction indicator is in the red/orange
“change” zone, replace the filter and reset the
restriction indicator.
To inspect and replace the filter and reset the restriction
indicator, do the following:
The air cleaner/filter assembly is located at the front of
the engine compartment.
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1. Loosen the screws on the cover of the housing and
lift up the cover.
2. Remove the air cleaner/filter from the housing. Care
should be taken to dislodge as little dirt as possible.
3. Clean the filter sealing surface and the housing.
4. Install the new engine air cleaner/filter.
5. Reinstall the cover and tighten the screws.
6. Reset the air cleaner/filter restriction indicator,
if equipped, by pressing the top button on the
indicator.SeeScheduled Maintenance on page 6-4to determine
when to replace the engine air cleaner/filter.
{CAUTION:
Operating the engine with the air cleaner/lter
off can cause you or others to be burned.
The air cleaner not only cleans the air; it
helps to stop ames if the engine backres.
If it is not there and the engine backres, you
could be burned. Do not drive with it off, and
be careful working on the engine with the
air cleaner/lter off.
Notice:If the air cleaner/lter is off, a backre can
cause a damaging engine re. And, dirt can easily get
into your engine, which will damage it. Always have
the air cleaner/lter in place when you are driving.
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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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Checking the Fluid Level
Prepare your vehicle as follows:
•Park your vehicle on a level place. Keep the
engine running.
•With the parking brake applied, place the shift lever
in PARK (P).
•With your foot on the brake pedal, run the engine
for at least one minute and shift to DRIVE (D).
Then shift to NEUTRAL (N) and then REVERSE (R)
to fill the hydraulic system. Then, put the shift
lever in PARK (P).
•Allow the engine to run at idle (500 – 800 rpm).
Slowly release the brake pedal.Then, without shutting off the engine, follow these steps:
Cold Check Procedure
The purpose of the cold check is to determine if the
transmission has enough fluid to be operated safely until
a hot check can be made. The fluid level rises as fluid
temperature increases. DO NOT fill above the COLD
CHECK band if the transmission fluid is below normal
operating temperatures.
1. Pull out the dipstick and wipe it with a clean rag or
paper towel. The transmission dipstick is located
near the center of the engine compartment. See
Engine Compartment Overview on page 5-18for
more information on location.
2. Push it back in all the way, wait three seconds and
then pull it back out again.
3. Check the fluid level reading. Repeat the check
procedure to verify the reading.
4. If the fluid level is within the COLD CHECK band, the
transmission may be operated until the fluid is hot
enough to perform a hot check. If the fluid level is not
within the COLD CHECK band, add or drain fluid as
necessary to bring the level into the middle of the
COLD CHECK band.
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5. Perform a hot check at the first opportunity after the
normal operating temperature of 160°F (71°C) to
200°F (93°C) is reached.
6. If the fluid level is in the acceptable range, push the
dipstick back in all the way.
Hot Check Procedure
The fluid must be hot to ensure an accurate check.
The fluid level rises as temperature increases.
1. Operate the transmission in DRIVE (D) until the
normal operating temperature of 160°F (71°C) to
200°F (93°C) is reached.
2. Pull out the dipstick and wipe it with a clean rag or
paper towel.
3. Push it back in all the way, wait three seconds
and then pull it back out again. Repeat the check
procedure to verify the reading.
4. Safe operating level is within the HOT RUN band
on the dipstick. The width of the HOT RUN band
represents approximately 1.06 quart (1.0 liter)
of fluid at normal operating temperature.
5. If the fluid level is not within the HOT RUN band,
add or drain fluid as necessary to bring the fluid
level to within the HOT RUN band.
6. If the fluid level is in the acceptable range, push the
dipstick back in all the way.
Consistency of Readings
Always check the fluid level at least twice using the
procedures described previously. Consistency
(repeatable readings) is important to maintaining proper
fluid level. If inconsistent readings persist, check the
transmission breather to be sure it is clean and
unclogged. If readings are still inconsistent, contact
your dealer.
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.
Add fluid 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
doesn’t take much fluid, generally less than one pint
(0.5 L).Don’t overll.
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 inRecommended
Fluids and Lubricants on page 6-15.
•After adding fluid, recheck the fluid level as described
under “How to Check.”
•When the correct fluid level is obtained, push the
dipstick back in all the way.
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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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Checking the Fluid Level
Prepare your vehicle as follows:
•Park your vehicle on a level place. Keep the engine
running.
•With the parking brake applied, place the shift lever
in PARK (P).
•With your foot on the brake pedal, move the shift
lever through each gear range, pausing for about
three seconds in each range. Then, position the shift
lever in PARK (P).
•Let the engine run at idle for three minutes or more.
Then, without shutting off the engine, follow these steps:The transmission dipstick is located near the center
of the engine compartment and will be labeled with the
graphic shown. SeeEngine Compartment Overview
on page 5-18for more information on location.
1. Flip the handle up and then pull out the dipstick
and wipe it with a clean rag or paper towel.
2. Push it back in all the way, wait three seconds and
then pull it back out again.
Check both sides of the dipstick, and read the lower
level. The fluid level must be in the COLD area for a
cold check or in the HOT or cross-hatched area for a
hot check. Be sure to keep the dipstick pointed down
to get an accurate reading.
3. If the fluid level is in the acceptable range, push the
dipstick in all the way, then flip the handle down to
lock the dipstick in place.
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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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