engine coolant GMC YUKON XL 2006 Owner's Manual

The coolant level should
be at or above the FULL
COLD mark. If it is not,
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 your vehicle is equipped with an electric engine
cooling fan, check the coolant temperature gage. If the
coolant temperature is approximately 232°F (111°C),
the electric cooling fan should be running. If it is
not, your vehicle needs service. Turn off the engine.
If your vehicle is equipped with an engine-driven cooling
fan, start the engine again and see if the fan speed
increases when idle speed is doubled by pushing the
accelerator pedal down. If it does not, your vehicle
needs service. Turn off the engine.
Notice:Engine damage from running your engine
without coolant is not covered by your warranty. See
Overheated Engine Protection Operating Mode on
page 5-30for information on driving to a safe place
in an emergency.
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.
5-32

How to Add Coolant to the Coolant
Surge Tank
If you have not found a problem yet, check to see if
coolant is visible in the surge tank. If coolant is visible
but the coolant level is not at or above the FULL COLD
mark, add a 50/50 mixture of clean, drinkable water
and 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.
SeeEngine Coolant on page 5-25for 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. 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.
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.
5-33

{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.3. Fill the coolant surge tank with the proper mixture,
to the FULL COLD mark.
5-34

4. With the coolant surge tank pressure cap off, start
the engine and let it run until you can feel the upper
radiator hose getting hot. Watch out for the
engine cooling fan.
By this time, the coolant level inside the coolant
surge tank may be lower. If the level is lower, add
more of the proper mixture to the coolant surge tank
until the level reaches the FULL COLD mark.
5. Then replace the pressure cap. Be sure the
pressure cap is hand-tight and fully seated.
Engine Fan Noise
If your vehicle is equipped with a clutched engine
cooling fan, when the clutch is engaged, the fan spins
faster to provide more air to cool the engine. In
most everyday driving conditions, the fan is spinning
slower and the clutch is not fully engaged. This improves
fuel economy and reduces fan noise. Under heavy
vehicle loading, trailer towing, and/or high outside
temperatures, the fan speed increases as the clutch
more fully engages, so you may hear an increase in
fan noise. This is normal and should not be mistaken
as the transmission slipping or making extra shifts.
It is merely the cooling system functioning properly.
The fan will slow down when additional cooling is not
required and the clutch disengages.
You may also hear this fan noise when you start the
engine. It will go away as the fan clutch partially
disengages.
If your vehicle is equipped with electric cooling fans, you
may hear the fans spinning at low speed during most
everyday driving. The fans may turn off if no cooling is
required. Under heavy vehicle loading, trailer towing,
and/or high outside temperatures, or if you are operating
your air conditioning system, the fans change to high
speed and you may hear an increase in fan noise.
This is normal and indicates that the cooling system
is functioning properly. The fans will change to low
speed when additional cooling is no longer required.
5-35

Windshield Washer Fluid
What to Use
When you need windshield washer uid, be sure to
read the manufacturer’s instructions before use. If you
will be operating your vehicle in an area where the
temperature may fall below freezing, use a uid that
has sufficient protection against freezing.
Adding Washer Fluid
Your vehicle has a low washer uid message that
comes on when the washer uid is low. The message
is displayed for 15 seconds at the start of each
ignition cycle. When the CHECK WASHER FLUID
message is displayed, you will need to add washer
uid to the windshield washer uid reservoir.
Open the cap with the
washer symbol on it.
Add washer uid until the
tank is full. SeeEngine
Compartment Overview
on page 5-12for reservoir
location.Notice:
When using concentrated washer uid, follow
the manufacturer’s instructions for adding
water.
Do not mix water with ready-to-use washer uid.
Water can cause the solution to freeze and
damage your washer uid tank and other parts
of the washer system. Also, water does not
clean as well as washer uid.
Fill your washer uid tank only three-quarters
full when it is very cold. This allows for
expansion if freezing occurs, which could
damage the tank if it is completely full.
Do not use engine coolant (antifreeze) in your
windshield washer. It can damage your washer
system and paint.
5-37

ApplicationCapacities
English Metric
Fuel Tank
Yukon 26.0 gal 98.4 L
Yukon XL (1500 Series) 31.0 gal 117.3 L
Yukon XL (2500 Series) 37.5 gal 140.0 L
Transfer Case Fluid 2.0 qts 1.9 L
Wheel Nut Torque 140 lb ft 190Y
†Oil lter should be changed at every oil change.
After rell, the level must be rechecked. Add enough engine coolant so that the uid is within the proper
operating range.
Engine Specications
Engine VIN Code Transmission Spark Plug Gap
VORTEC™ 4800 V8 V Automatic 0.040 in (1.01 mm)
VORTEC™ 5300 V8 T Automatic 0.040 in (1.01 mm)
VORTEC™ 5300 V8 Z Automatic 0.040 in (1.01 mm)
VORTEC™ 6000 V8 U Automatic 0.040 in (1.01 mm)
VORTEC™ 8100 V8 G Automatic 0.060 in (1.52 mm)
5-115

Scheduled Maintenance
Service MaintenanceIMaintenanceII
Change engine oil and lter. SeeEngine Oil on page 5-15. Reset oil life system.
SeeEngine Oil Life System on page 5-18.An Emission Control Service.••
Lubricate chassis components.See footnote #.••
Visually check for any leaks or damage.See footnote (j).••
Inspect engine air cleaner lter or change indicator (if equipped). If necessary,
replace lter. SeeEngine Air Cleaner/Filter on page 5-20.See footnote (l).•
Rotate tires and check ination pressures and wear. SeeTire Inspection and
Rotation on page 5-68and “Tire Wear Inspection” inAt Least Once a Month
on page 6-10.••
Inspect brake system.See footnote (a).••
Check engine coolant and windshield washer uid levels and add uid as
needed.••
Perform any needed additional services. See “Additional Required Services”
in this section.••
Inspect suspension and steering components.See footnote (b).•
Inspect engine cooling system.See footnote (c).•
Inspect wiper blades.See footnote (d).•
Inspect restraint system components.See footnote (e).•
Lubricate body components.See footnote (f).•
Check transmission uid level and add uid as needed.•
6-5

Applying silicone grease on weatherstrips with a clean
cloth will make them last longer, seal better, and
not stick or squeak.
(g)Check vent hose at transfer case for kinks and
proper installation.
(h)Change automatic transmission uid and 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.
(i)Drain, ush, and rell cooling system. This service
can be complex; you should have your dealer perform
this service. See Engine Coolant on page 5-25 for
what to use. Inspect hoses. Clean radiator, condenser,
pressure cap, and ller neck. Pressure test the
cooling system and pressure cap.
(j)A uid loss in any vehicle system could indicate a
problem. Have the system inspected and repaired
and the uid level checked. Add uid if needed.(k)Inspect system. Check all fuel and vapor lines
and hoses for proper hook-up, routing, and condition.
Check that the purge valve works properly, if equipped.
Replace as needed.
(l)If you drive regularly under dusty conditions, inspect
the lter at each engine oil change.
(m)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 specied 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 uids or lubricants are added to your
vehicle, make sure they are the proper ones, as shown
inRecommended Fluids and Lubricants on page 6-13.
6-9

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 5-15for 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.
Engine Coolant Level Check
Check the engine coolant level and add
DEX-COOL®coolant mixture if necessary.
SeeEngine Coolant on page 5-25for further details.
Windshield Washer Fluid Level Check
Check the windshield washer uid level in the
windshield washer uid reservoir and add the
proper uid if necessary.
At Least Once a Month
Tire Ination Check
Visually inspect your vehicle’s tires and make sure they
are inated to the correct pressures. Do not forget to
check the spare tire. SeeTires on page 5-57for further
details. Check to make sure the spare tire is stored
securely. SeeChanging a Flat Tire on page 5-76.
Tire Wear Inspection
Tire rotation may be required for high mileage highway
drivers prior to the Engine Oil Life System service
notication. Check the tires for wear and, if necessary,
rotate the tires. SeeTire Inspection and Rotation
on page 5-68.
6-10

Recommended Fluids and
Lubricants
Fluids and lubricants identied below by name,
part number, or specication may be obtained
from your dealer.
Usage Fluid/Lubricant
Engine OilEngine oil which meets
GM Standard GM6094M and
displays the American Petroleum
Institute Certied for Gasoline
Engines starburst symbol.
GM Goodwrench
®oil meets all
the requirements for your vehicle.
To determine the proper viscosity
for your vehicle’s engine, see
Engine Oil on page 5-15.
Engine Coolant50/50 mixture of clean, drinkable
water and use only DEX-COOL
®
Coolant. SeeEngine Coolant
on page 5-25.
Usage Fluid/Lubricant
Hydraulic Brake
SystemDelco
®Supreme 11 Brake Fluid
or equivalent DOT-3 brake uid.
Windshield
WasherGM Optikleen
®Washer Solvent.
Power Steering
SystemGM Power Steering Fluid
(GM Part No. U.S. 89021184, in
Canada 89021186).
Automatic
TransmissionDEXRON
®-VI Automatic
Transmission Fluid.
Key Lock
CylindersMulti-Purpose Lubricant, Superlube
(GM Part No. U.S. 12346241, in
Canada 10953474).
Chassis
LubricationChassis Lubricant
(GM Part No. U.S. 12377985, in
Canada 88901242) or lubricant
meeting requirements of NLGI #2,
Category LB or GC-LB.
6-13