oil GMC YUKON 2008 Owner's Guide

If you get the ENGINE OVERHEATED STOP ENGINE or
the ENGINE OVERHEATED IDLE ENGINE message
with no sign of steam, try this for a minute or so:
1. If the vehicle has an air conditioner and it is on,
turn it off.
2. Turn on the heater to the highest temperature and
at the highest fan speed and open the windows as
necessary.
3. 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.
If you no longer have the overheat warning, you can
drive. Just to be safe, drive slower for about 10 minutes.
If the warning does not come back on, you can drive
normally.
If the warning continues, pull over, stop, and park your
vehicle immediately.
If there is still no sign of steam and your vehicle has 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 ve minutes while parked.
If there is still no sign of steam and your vehicle has an
electric cooling fan, idle the engine for ve minutes
while parked.If you still have the warning, turn off the engine and get
everyone out of the vehicle until it cools down. Also,
see “Overheated Engine Protection Operating Mode”
later in this section.
You might decide not to lift the hood but to get service
help right away.
Overheated Engine Protection
Operating Mode
If an overheated engine condition exists and the
ENGINE POWER IS REDUCED message is displayed,
an overheat protection mode which alternates ring
groups of cylinders helps prevent engine damage. In this
mode, you will notice a loss in power and engine
performance. This operating mode allows your vehicle
to be driven to a safe place in an emergency. Driving
extended miles (km) and/or towing a trailer in the
overheat protection mode should be avoided.
Notice:After driving in the overheated engine
protection operating mode, to avoid engine damage,
allow the engine to cool before attempting any
repair. The engine oil will be severely degraded.
Repair the cause of coolant loss, change the oil and
reset the oil life system. SeeEngine Oil on
page 5-15.
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Cooling System
If your vehicle is a Two-mode Hybrid, see the Two-mode
Hybrid manual for more information.
When you decide it is safe to lift the hood, here is what
you will see:
A. Coolant Surge Tank
B. Coolant Surge Tank Pressure Cap
C. Engine Cooling Fan(s){CAUTION:
An electric fan under the hood can start up
and injure you even when the engine is not
running. Keep hands, clothing, and tools away
from any underhood electric fan.
If the coolant inside the coolant surge tank is boiling, do
not do anything else until it cools down. If possible,
the vehicle should be parked on a level surface. Check
the coolant level after the system cools down. Some
amount of coolant may be lost due to overheating.
5.3L Engine (4.8L and 6.0L Similar)
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{CAUTION:
Adding only plain water to the cooling system
can be dangerous. Plain water, or some other
liquid such as alcohol, can boil before the
proper coolant mixture will. The vehicle’s
coolant warning system is set for the proper
coolant mixture. With plain water or the wrong
mixture, the engine could get too hot but you
would not get the overheat warning. The
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.
{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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What to Add
When you do need brake uid, use only DOT-3 brake
uid. Use new brake uid from a sealed container
only. SeeRecommended Fluids and Lubricants on
page 6-13.
Always clean the brake uid reservoir cap and the area
around the cap before removing it. This helps keep
dirt from entering the reservoir.
{CAUTION:
With the wrong kind of uid in the brake
hydraulic system, the brakes might not work
well. This could cause a crash. Always use the
proper brake uid.Notice:
Using the wrong uid can badly damage brake
hydraulic system parts. For example, just a
few drops of mineral-based oil, such as engine
oil, in the brake hydraulic system can damage
brake hydraulic system parts so badly that they
will have to be replaced. Do not let someone
put in the wrong kind of uid.
If you spill brake uid on your vehicle’s painted
surfaces, the paint nish can be damaged. Be
careful not to spill brake uid on your vehicle. If
you do, wash it off immediately. SeeWashing
Your Vehicle on page 5-111.
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Tire Terminology and Denitions
Air Pressure:The amount of air inside the
tire pressing outward on each square inch of the
tire. Air pressure is expressed in pounds per
square inch (psi) or kilopascal (kPa).
Accessory Weight
:This means the combined
weight of optional accessories. Some examples of
optional accessories are, automatic transmission,
power steering, power brakes, power windows,
power seats, and air conditioning.
Aspect Ratio
:The relationship of a tire’s height
to its width.
Belt
:A rubber coated layer of cords that is
located between the plies and the tread. Cords
may be made from steel or other reinforcing
materials.
Bead
:The tire bead contains steel wires wrapped
by steel cords that hold the tire onto the rim.
Bias Ply Tire
:A pneumatic tire in which the plies
are laid at alternate angles less than 90 degrees
to the centerline of the tread.Cold Tire Pressure
:The amount of air pressure
in a tire, measured in pounds per square inch
(psi) or kilopascals (kPa) before a tire has built up
heat from driving. SeeInflation - Tire Pressure
on page 5-72.
Curb Weight
:The weight of a motor vehicle with
standard and optional equipment including the
maximum capacity of fuel, oil, and coolant,
but without passengers and cargo.
DOT Markings
:A code molded into the sidewall
of a tire signifying that the tire is in compliance
with the U.S. Department of Transportation (DOT)
motor vehicle safety standards. The DOT code
includes the Tire Identication Number (TIN),
an alphanumeric designator which can also identify
the tire manufacturer, production plant, brand,
and date of production.
GVWR
:Gross Vehicle Weight Rating. See
Loading Your Vehicle on page 4-35.
GAWR FRT
:Gross Axle Weight Rating for the
front axle. SeeLoading Your Vehicle on
page 4-35.
GAWR RR
:Gross Axle Weight Rating for the rear
axle. SeeLoading Your Vehicle on page 4-35.
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{CAUTION:
Never use oil or grease on studs or nuts.
Because the nuts might come loose. The
vehicle’s wheel could fall off, causing a crash.
8. Put the wheel nuts back on with the rounded end
of the nuts toward the wheel after mounting the
spare tire.
9. Tighten each wheel nut by hand. Then use the
wheel wrench to tighten the nuts until the wheel
is held against the hub.
10. Turn the wheel wrench counterclockwise to lower
the vehicle. Lower the jack completely.
{CAUTION:
Incorrect or improperly tightened wheel nuts
can cause the wheel to come loose and even
come off. This could lead to a crash. If you
have to replace them, be sure to get new
original equipment wheel nuts. Stop
somewhere as soon as you can and have the
nuts tightened with a torque wrench to the
proper torque specication. SeeCapacities
and Specifications on page 5-124for wheel nut
torque specication.
Notice:Improperly tightened wheel nuts can lead
to brake pulsation and rotor damage. To avoid
expensive brake repairs, evenly tighten the wheel
nuts in the proper sequence and to the proper
torque specication. SeeCapacities and
Specifications on page 5-124for the wheel nut
torque specication.
5-99

After installing the spare tire on your vehicle, you should
stop as soon as possible and make sure the spare
tire is correctly inated. Have the damaged or at road
tire repaired or replaced as soon as you can and
installed back onto your vehicle. This way, the spare tire
will be available in case you need it again.
Do not mix tires and wheels of different sizes, because
they will not t. Keep your spare tire and its wheel
together. If your vehicle has a spare tire that does not
match your vehicle’s original road tires and wheels
in size and type, do not include the spare in the
tire rotation.
Appearance Care
Interior Cleaning
Your vehicle’s interior will continue to look its best if it is
cleaned often. Although not always visible, dust and
dirt can accumulate on your upholstery. Dirt can damage
carpet, fabric, leather, and plastic surfaces. Regular
vacuuming is recommended to remove particles
from your upholstery. It is important to keep your
upholstery from becoming and remaining heavily soiled.
Soils should be removed as quickly as possible. Your
vehicle’s interior may experience extremes of heat
that could cause stains to set rapidly.Lighter colored interiors may require more frequent
cleaning. Use care because newspapers and garments
that transfer color to your home furnishings may also
transfer color to your vehicle’s interior.
When cleaning your vehicle’s interior, only use cleaners
specically designed for the surfaces being cleaned.
Permanent damage may result from using cleaners on
surfaces for which they were not intended. Use glass
cleaner only on glass. Remove any accidental over-spray
from other surfaces immediately. To prevent over-spray,
apply cleaner directly to the cleaning cloth.
Notice:If you use abrasive cleaners when cleaning
glass surfaces on your vehicle, you could scratch
the glass and/or cause damage to the rear window
defogger. When cleaning the glass on your
vehicle, use only a soft cloth and glass cleaner.
Many cleaners contain solvents that may become
concentrated in your vehicle’s breathing space. Before
using cleaners, read and adhere to all safety
instructions on the label. While cleaning your vehicle’s
interior, maintain adequate ventilation by opening
your vehicle’s doors and windows.
Dust may be removed from small buttons and knobs
using a small brush with soft bristles.
Your dealer/retailer has a product for cleaning your
vehicle’s glass. Should it become necessary, you can
also obtain a product from your dealer/retailer to remove
odors from your vehicle’s upholstery.
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Do not clean your vehicle using the following cleaners
or techniques:
Never use a knife or any other sharp object to
remove a soil from any interior surface.
Never use a stiff brush. It can cause damage to
your vehicle’s interior surfaces.
Never apply heavy pressure or rub aggressively
with a cleaning cloth. Use of heavy pressure
can damage your interior and does not improve the
effectiveness of soil removal.
Use only mild, neutral-pH soaps. Avoid laundry
detergents or dishwashing soaps with degreasers.
Using too much soap will leave a residue that
leaves streaks and attracts dirt. For liquid cleaners,
about 20 drops per gallon (3.78 L) of water is a
good guide.
Do not heavily saturate your upholstery while
cleaning.
Damage to your vehicle’s interior may result from
the use of many organic solvents such as naptha,
alcohol, etc.
Fabric/Carpet
Use a vacuum cleaner with a soft brush attachment
frequently to remove dust and loose dirt. A canister
vacuum with a beater bar in the nozzle may only
be used on oor carpet and carpeted oor mats. For
soils, always try to remove them rst with plain water or
club soda. Before cleaning, gently remove as much
of the soil as possible using one of the following
techniques:
For liquids: gently blot the remaining soil with a
paper towel. Allow the soil to absorb into the
paper towel until no more can be removed.
For solid dry soils: remove as much as possible
and then vacuum.
To clean, use the following instructions:
1. Saturate a lint-free, clean white cloth with water or
club soda.
2. Wring the cloth to remove excess moisture.
3. Start on the outside edge of the soil and gently rub
toward the center. Continue cleaning, using a clean
area of the cloth each time it becomes soiled.
4. Continue to gently rub the soiled area until the
cleaning cloth remains clean.
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5. If the soil is not completely removed, use a mild
soap solution and repeat the cleaning process
that was used with plain water.
If any of the soil remains, a commercial fabric cleaner or
spot lifter may be necessary. When a commercial
upholstery cleaner or spot lifter is to be used, test a
small hidden area for colorfastness rst. If the locally
cleaned area gives any impression that a ring formation
may result, clean the entire surface.
After the cleaning process has been completed, a paper
towel can be used to blot excess moisture from the
fabric or carpet.
Leather
A soft cloth dampened with water can be used to
remove dust. If a more thorough cleaning is necessary,
a soft cloth dampened with a mild soap solution can
be used. Allow the leather to dry naturally. Do not use
heat to dry. Never use steam to clean leather. Never
use spot lifters or spot removers on leather. Many
commercial leather cleaners and coatings that are sold
to preserve and protect leather may permanently
change the appearance and feel of your leather and are
not recommended. Do not use silicone or wax-based
products, or those containing organic solvents to clean
your vehicle’s interior because they can alter the
appearance by increasing the gloss in a non-uniform
manner. Never use shoe polish on leather.
Instrument Panel, Vinyl, and Other
Plastic Surfaces
A soft cloth dampened with water may be used to
remove dust. If a more thorough cleaning is necessary,
a clean soft cloth dampened with a mild soap solution
can be used to gently remove dust and dirt. Never use
spot lifters or removers on plastic surfaces. Many
commercial cleaners and coatings that are sold to
preserve and protect soft plastic surfaces may
permanently change the appearance and feel of your
interior and are not recommended. Do not use silicone
or wax-based products, or those containing organic
solvents to clean your vehicle’s interior because
they can alter the appearance by increasing the gloss in
a non-uniform manner.
Some commercial products may increase gloss on your
instrument panel. The increase in gloss may cause
annoying reections in the windshield and even make it
difficult to see through the windshield under certain
conditions.
5-110

Cleaning Exterior Lamps/Lenses
Use only lukewarm or cold water, a soft cloth and a car
washing soap to clean exterior lamps and lenses.
Follow instructions underWashing Your Vehicle on
page 5-111.
Finish Care
Occasional waxing or mild polishing of your vehicle by
hand may be necessary to remove residue from the
paint nish. You can get approved cleaning products
from your dealer/retailer. SeeVehicle Care/Appearance
Materials on page 5-115.
If your vehicle has a basecoat/clearcoat paint nish, the
clearcoat gives more depth and gloss to the colored
basecoat. Always use waxes and polishes that are
non-abrasive and made for a basecoat/clearcoat paint
nish.
Notice:Machine compounding or aggressive
polishing on a basecoat/clearcoat paint nish may
damage it. Use only non-abrasive waxes and
polishes that are made for a basecoat/clearcoat
paint nish on your vehicle.Foreign materials such as calcium chloride and other
salts, ice melting agents, road oil and tar, tree sap, bird
droppings, chemicals from industrial chimneys, etc.,
can damage your vehicle’s nish if they remain
on painted surfaces. Wash the vehicle as soon as
possible. If necessary, use non-abrasive cleaners that
are marked safe for painted surfaces to remove
foreign matter.
Exterior painted surfaces are subject to aging, weather
and chemical fallout that can take their toll over a
period of years. You can help to keep the paint nish
looking new by keeping your vehicle garaged or covered
whenever possible.
Protecting Exterior Bright Metal Parts
Bright metal parts should be cleaned regularly to keep
their luster. Washing with water is all that is usually
needed. However, you may use chrome polish on
chrome or stainless steel trim, if necessary.
Use special care with aluminum trim. To avoid damaging
protective trim, never use auto or chrome polish,
steam or caustic soap to clean aluminum. A coating of
wax, rubbed to high polish, is recommended for all
bright metal parts.
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