2006 GMC SIERRA adding oil

How to Add Automatic
Transmission Fluid
Refer to the Maintenance Schedule to determine what
kind of transmission uid to use. SeeRecommended
Fluids and Lubricants (Gasoline Engine) on page 6-14.
Add uid only after checking the transmission uid
while it is hot. A cold check is used only as a reference.
If the uid level is low, add only enough of the proper
uid to bring the level up to the HOT area for a hot
check. It does not take much uid, generally less than
one pint (0.5 L). Do not 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 in
Recommended Fluids and Lubricants (Gasoline
Engine) on page 6-14.
After adding uid, recheck the uid level as
described under “How to Check Automatic
Transmission Fluid,” earlier in this section.
When the correct uid level is obtained, push the
dipstick back in all the way; then ip the handle
down to lock the dipstick in place.
Automatic Transmission Fluid
(Allison Transmission
®)
When to Check and Change Automatic
Transmission Fluid
A good time to check your automatic transmission uid
level is when the engine oil is changed.
Change the uid and lter at the intervals listed in
Additional Required Services (Gasoline Engine) on
page 6-7, and be sure to use the transmission uid
listed inRecommended Fluids and Lubricants
(Gasoline Engine) on page 6-14.
How to Check Automatic
Transmission Fluid
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.
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How to Add Automatic
Transmission Fluid
Refer to the Maintenance Schedule to determine what
kind of transmission uid to use. SeeRecommended
Fluids and Lubricants (Gasoline Engine) on page 6-14.
Add uid only after checking the transmission uid
while it is hot. A cold check is used only as a reference.
If the uid level is low, add only enough of the proper
uid to bring the level up to the HOT area for a hot
check. It does not take much uid, generally less than
one pint (0.5 L). Do not 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 (Gasoline Engine) on
page 6-14.
After adding uid, recheck the uid level as described
under “How to Check Automatic Transmission Fluid,”
earlier in this section.
When the correct uid level is obtained, push the
dipstick back in all the way.
Manual Transmission Fluid
When to Check Manual
Transmission Fluid
A good time to have your manual transmission uid
checked is when the engine oil is changed. See
Additional Required Services (Gasoline Engine)
on page 6-7to nd out when to change your
transmission uid.
How to Check Manual
Transmission Fluid
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.
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.
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What to Use
Use a mixture of one-half clean, drinkable water and
one-half DEX-COOL®coolant which will not damage
aluminum parts. If you use this coolant mixture, you do
not 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
(Gasoline Engine) on page 6-14for more information.
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 5-14
for more information on 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.
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{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 a proper coolant.
Notice:In cold weather, water can freeze and crack
the engine, radiator, heater core and other parts.
Use the recommended coolant and the proper
coolant mixture.
{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.
1. You can remove the
coolant surge tank
pressure cap when
the cooling system,
including the coolant
surge tank pressure
cap and upper radiator
hose, is no longer hot.
Turn the pressure cap slowly counterclockwise
about one full turn. If you hear a hiss, wait for that to
stop. A hiss means there is still some pressure left.
2. Then keep turning the pressure cap slowly, and
remove it.
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