2006 CHEVROLET DURAMAX cooling

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
5-1
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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.
5-34
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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.
5-35
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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.
5-37
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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.
Checking Coolant
The coolant recovery tank
is located near the center
of the engine compartment.
SeeEngine Compartment
Overview on page 5-18
for more information on
its location.
{CAUTION:
Turning the radiator pressure cap when the
engine and radiator are hot can allow steam
and scalding liquids to blow out and burn you
badly. With the coolant recovery tank, you will
almost never have to add coolant at the
radiator. Never turn the radiator 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
COLD FILL mark.
5-38
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If you get the overheat warning with no sign of steam,
try this for a minute or so:
1. In heavy traffic, let the engine idle in NEUTRAL (N)
while stopped. If it is safe to do so, pull off the road,
shift to PARK (P) or NEUTRAL (N), and let the
engine idle.
2. Turn on your heater to full hot at the highest fan
speed and open the window as necessary.
If you no longer have the overheat warning, you can
drive. Just to be safe, drive slower for about 10 minutes.
If the warning doesn’t come back on, you can drive
normally.
If the warning continues, pull over, stop, and park your
vehicle right away.
If there’s still no sign of steam and your vehicle is
equipped with an engine driven cooling fan, push down
the accelerator until the engine speed is about twice as
fast as normal idle speed for at least three minutes while
you’re parked. If there is no sign of steam and your
vehicle is equipped with an electric cooling fan, idle the
engine for three minutes while you’re parked. If you still
have the warning,turn off the engine and get everyone
out of the vehicleuntil it cools down.
You may decide not to lift the hood but to get service
help right away.Cooling System
Pickup Models
When you decide it’s safe to lift the hood, here’s what
you’ll see:
A. Coolant Surge Tank Pressure Cap
B. Coolant Surge Tank
C. Engine Fan
If the coolant inside the coolant surge tank is boiling,
don’t do anything else until it cools down. The vehicle
should be parked on a level surface.
5-41
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The coolant level should
be at or above the FULL
COLD mark. If it isn’t, 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 and 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. If
your vehicle is equipped with an engine driven cooling
fan, the engine cooling fan speed should increase when
idle speed is doubled by pushing the accelerator pedal
down. If it doesn’t, your vehicle needs service. Turn off
the engine.
Notice:Engine damage from running your engine
without coolant is not covered by your warranty.
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 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.
5-42
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How to Add Coolant to the Coolant
Surge Tank
Notice:The diesel engine has a specic coolant
ll procedure. Failure to follow this procedure could
cause your engine to overheat and be severely
damaged.
If you haven’t found a problem yet, check to see
if coolant is visible in the surge tank. If coolant is visible
but the coolant level isn’t at or above the FULL COLD
mark, add a 50/50 mixture ofclean, drinkable waterand
DEX-COOL
®coolant at the coolant surge tank, but
be sure the cooling system, including the coolant surge
tank pressure cap, is cool before you do it. See
Engine Coolant on page 5-34for more information.
If no coolant is visible in the surge tank, add coolant
as follows:
{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
coolant surge tank pressure cap — even a
little — they can come out at high speed.
CAUTION: (Continued)
CAUTION: (Continued)
Never turn the cap when the cooling system,
including the coolant surge tank pressure cap,
is hot. Wait for the cooling system and coolant
surge tank pressure cap to cool if you ever
have to turn the pressure cap.
{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.
5-43
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