2006 CHEVROLET DURAMAX coolant temperature

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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(n)Change clutch uid (or every 24 months, whichever
occurs rst).
(p)Change automatic transmission uid and external
transmission lter 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.
(q)Check vent hose at transfer case for kinks and
proper installation.
(r)Drain, ush, and rell cooling system. This service
can be complex; you should have your dealer perform
this service. See Engine Coolant on page 5-34 for
what to use. Inspect hoses. Clean radiator, condenser,
van model fuel operated heater (if equipped), pressure
cap, and ller neck. Pressure test the cooling system
and pressure cap. For van models, see Fuel Operated
Heater (FOH) (Van Models Only) on page 2-8.
(s)Visually inspect belt for fraying, excessive cracks,
or obvious damage. Replace belt if necessary.Owner Checks and Services
These owner checks and services should be performed
at the intervals specified to help ensure the safety,
dependability, and emission control performance of your
vehicle. Your GM Goodwrench
®dealer can assist you
with these checks and services.
Be sure any necessary repairs are completed at once.
Whenever any fluids or lubricants are added to your
vehicle, make sure they are the proper ones, as shown
inRecommended Fluids and Lubricants on page 6-15.
At Each Fuel Fill
It is important to perform these underhood checks at
each fuel ll.
Engine Oil Level Check
Check the engine oil level and add the proper oil if
necessary. SeeEngine Oil on page 5-21for further
details.
Notice:It is important to check your oil regularly
and keep it at the proper level. Failure to keep your
engine oil at the proper level can cause damage
to your engine not covered by your warranty.
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