engine GMC YUKON 2008 Owners Manual

Checking Things Under
the Hood
{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.
{CAUTION:
Things that burn can get on hot engine parts
and start a re. These include liquids like fuel,
oil, coolant, brake uid, windshield washer and
other uids, and plastic or rubber. You or
others could be burned. Be careful not to drop
or spill things that will burn onto a hot engine.
5-12

Engine Compartment Overview
If your vehicle is a Two-mode Hybrid, see the Two-mode Hybrid manual for more information.
When you open the hood on the 5.3L engine (4.8L and 6.0L similar), here is what you will see:
5-14

A. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 5-19.
B. Air Filter Restriction Indicator (If Equipped). See
Engine Air Cleaner/Filter on page 5-19.
C. Coolant Surge Tank and Pressure Cap. SeeCooling
System on page 5-34andCoolant Surge Tank
Pressure Cap on page 5-31.
D. Remote Positive (+) Terminal. SeeJump Starting on
page 5-46.
E. Battery. SeeBattery on page 5-45.
F. Engine Oil Fill Cap. See “When to Add Engine Oil”
underEngine Oil on page 5-15.
G. Automatic Transmission Dipstick. See “Checking the
Fluid Level” underAutomatic Transmission Fluid
(4-Speed Transmission) on page 5-22orAutomatic
Transmission Fluid (6-Speed Transmission) on
page 5-24.
H. Remote Negative (−) Terminal (Out of View). See
Jump Starting on page 5-46.
I. Engine Oil Dipstick (Out of View). See “Checking
Engine Oil” underEngine Oil on page 5-15.
J. Engine Cooling Fan. SeeCooling System on
page 5-34.
K. Power Steering Fluid Reservoir. SeePower Steering
Fluid on page 5-39.L. Brake Master Cylinder Reservoir. See “Brake Fluid”
underBrakes on page 5-41.
M. Underhood Fuse Block. SeeUnderhood Fuse Block
on page 5-120.
N. Windshield Washer Fluid Reservoir. See “Adding
Washer Fluid” underWindshield Washer Fluid
on page 5-40.
Engine Oil
Checking Engine Oil
It is a good idea to check the engine oil every time you
get fuel. In order to get an accurate reading, the oil
must be warm and the vehicle must be on level ground.
The engine oil dipstick handle is a yellow loop. See
Engine Compartment Overview on page 5-14for
the location of the engine oil dipstick.
1. Turn off the engine and give the oil several minutes
to drain back into the oil pan. If you do not do this,
the oil dipstick might not show the actual level.
2. Pull out the dipstick and clean it with a paper towel
or cloth, then push it back in all the way. Remove it
again, keeping the tip down, and check the level.
5-15

When to Add Engine Oil
If the oil is below the cross-hatched area at the tip of
the dipstick, add at least one quart/liter of the
recommended oil. This section explains what kind of oil
to use. For engine oil crankcase capacity, see
Capacities and Specifications on page 5-124.
Notice:Do not add too much oil. If the engine has
so much oil that the oil level gets above the
cross-hatched area that shows the proper operating
range, the engine could be damaged.SeeEngine Compartment
Overview on page 5-14for
the location of the
engine oil ll cap.
Be sure to add enough oil to put the level somewhere in
the proper operating range. Push the dipstick all the
way back in when you are through.
5-16

What Kind of Engine Oil to Use
Look for three things:
GM6094M
Your vehicle’s engine requires oil meeting GM
Standard GM6094M. Look for and use only an oil
that meets GM Standard GM6094M.
SAE 5W-30
As shown in the viscosity chart, SAE 5W-30 is best
for your vehicle.These numbers on an oil container show its
viscosity, or thickness. Do not use other viscosity
oils such as SAE 20W-50.
Oils meeting these
requirements should
have the starburst
symbol on the container.
This symbol indicates
that the oil has
been certied by the
American Petroleum
Institute (API).
Look for this information on the oil container, and use
only those oils that are identied as meeting GM
Standard GM6094M and have the starburst symbol on
the front of the oil container.
Notice:Use only engine oil identied as meeting
GM Standard GM6094M and showing the American
Petroleum Institute Certied For Gasoline Engines
starburst symbol. Failure to use the recommended
oil can result in engine damage not covered by
your warranty.
If you are in an area of extreme cold, where the
temperature falls below−20°F (−29°C), it is
recommended that you use either an SAE 5W-30
synthetic oil or an SAE 0W-30 oil. Both provide easier
cold starting and better protection for the engine at
extremely low temperatures.
5-17

Engine Oil Additives
Do not add anything to the oil. The recommended oils
with the starburst symbol that meet GM Standard
GM6094M are all you need for good performance and
engine protection.
Engine Oil Life System
When to Change Engine Oil
Your vehicle has a computer system that lets you know
when to change the engine oil and lter. This is
based on engine revolutions and engine temperature,
and not on mileage. Based on driving conditions,
the mileage at which an oil change will be indicated can
vary considerably. For the oil life system to work
properly, you must reset the system every time the oil is
changed.
When the system has calculated that oil life has been
diminished, it will indicate that an oil change is
necessary. A CHANGE ENGINE OIL SOON message
will come on. SeeDIC Warnings and Messages on
page 3-64. Change the oil as soon as possible within the
next 600 miles (1 000 km). It is possible that, if youare driving under the best conditions, the oil life system
might not indicate that an oil change is necessary for
over a year. However, the engine oil and lter must be
changed at least once a year and at this time the
system must be reset. Your dealer/retailer has trained
service people who will perform this work using genuine
parts and reset the system. It is also important to
check the oil regularly and keep it at the proper level.
If the system is ever reset accidentally, you must change
the oil at 3,000 miles (5 000 km) since your last oil
change. Remember to reset the oil life system whenever
the oil is changed.
How to Reset the Engine Oil Life
System
The Engine Oil Life System calculates when to change
the engine oil and lter based on vehicle use.
Whenever the oil is changed, reset the system so it can
calculate when the next oil change is required. If a
situation occurs where you change the oil prior
to a CHANGE ENGINE OIL SOON message coming
on, reset the system.
5-18

Always reset the engine oil life to 100% after every oil
change. It will not reset itself. To reset the Engine
Oil Life System:
1. Display the OIL LIFE REMAINING on the DIC. If
your vehicle does not have DIC buttons, the
vehicle must be in PARK (P) to access this display.
SeeDIC Operation and Displays (With DIC
Buttons) on page 3-56orDIC Operation and
Displays (Without DIC Buttons) on page 3-61.
2. Press and hold the SET/RESET button on the DIC,
or the trip odometer reset stem if your vehicle does
not have DIC buttons, for more than ve seconds.
The oil life will change to 100%.
If the CHANGE ENGINE OIL SOON message comes
back on when you start your vehicle, the Engine Oil Life
System has not reset. Repeat the procedure.
What to Do with Used Oil
Used engine oil contains certain elements that can be
unhealthy for your skin and could even cause cancer.
Do not let used oil stay on your skin for very long. Clean
your skin and nails with soap and water, or a good
hand cleaner. Wash or properly dispose of clothing or
rags containing used engine oil. See the manufacturer’s
warnings about the use and disposal of oil products.Used oil can be a threat to the environment. If you
change your own oil, be sure to drain all the oil from the
lter before disposal. Never dispose of oil by putting it
in the trash, pouring it on the ground, into sewers, or into
streams or bodies of water. Instead, recycle it by
taking it to a place that collects used oil. If you have a
problem properly disposing of used oil, ask your
dealer/retailer, a service station, or a local recycling
center for help.
Engine Air Cleaner/Filter
SeeEngine Compartment
Overview on page 5-14for
the location of the
engine air cleaner/lter and
the air lter restriction
indicator, if the vehicle
has one.
5-19

When to Inspect the Engine Air
Cleaner/Filter
If your vehicle has an air lter restriction indicator, it lets
you know when the engine air cleaner/lter needs to
be replaced. On vehicles with a restriction indicator, you
should inspect the air lter restriction indicator at
every oil change and replace the engine air cleaner/lter
when the indicator tells you to.
On vehicles without an air lter restriction indicator,
inspect the air cleaner/lter at the MaintenanceII
intervals and replace it at the rst oil change after each
50,000 mile (80 000 km) interval. SeeScheduled
Maintenance on page 6-4for more information. If you
are driving in dusty/dirty conditions, inspect the lter
at each engine oil change.
How to Inspect the Engine Air
Cleaner/Filter
Vehicles With an Air Filter Restriction
Indicator
Locate the air lter restriction indicator on the engine air
cleaner/lter cover. When the indicator turns black or
is in the red/orange “change” zone, replace the lter and
reset the indicator. See the steps following to replace
the engine air cleaner/lter and to reset the air lter
restriction indicator.
Vehicles Without an Air Filter Restriction
Indicator
To inspect the air cleaner/lter, remove the engine air
cleaner/lter from the vehicle by following Steps 1
through 6. When you have the engine air cleaner/lter
removed, lightly shake it to release loose dust and dirt. If
the engine air cleaner/lter remains caked with dirt, a
new lter is required.
Replacing the Engine Air Cleaner/Filter
and Resetting the Air Filter Restriction
Indicator
1. Locate the air
cleaner/lter assembly.
SeeEngine
Compartment Overview
on page 5-14.
2. Loosen the four screws on the cover of the housing
and lift up the cover.
5-20

3. Remove the engine air cleaner/lter from the
housing. Care should be taken to dislodge as
little dirt as possible.
4. Clean the engine air cleaner/lter sealing surfaces
and the housing.5. Inspect or replace the engine air cleaner/lter.
6. Reinstall the cover and tighten the screws.
7. Reset the air lter restriction indicator, if the vehicle
has one, by pressing the top button on the indicator.
{CAUTION:
Operating the engine with the air cleaner/lter
off can cause you or others to be burned. The
air cleaner not only cleans the air; it helps to
stop ames if the engine backres. If it is not
there and the engine backres, you could be
burned. Do not drive with it off, and be careful
working on the engine with the air cleaner/
lter off.
5-21

Automatic Transmission Fluid
(4-Speed 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 on page 6-6, and be sure
to use the transmission uid listed inRecommended
Fluids and Lubricants on page 6-13.
How to Check Automatic
Transmission Fluid
Because this operation can be a little difficult, you may
choose to have this done at the dealer/retailer 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.
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
parts 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.Wait at least 30 minutes before checking the
transmission uid level if you have been driving:
When outside temperatures are above 90°F (32°C).
At high speed for quite a while.
In heavy traffic — especially in hot weather.
While pulling a trailer.
To get the right reading, the uid should be at normal
operating temperature, which is 180°F to 200°F
(82°C to 93°C).
Get the vehicle warmed up by driving about 15 miles
(24 km) when outside temperatures are above 50°F
(10°C). If it is colder than 50°F (10°C), drive the vehicle
in THIRD (3) until the engine temperature gage
moves and then remains steady for 10 minutes.
A cold uid check can be made after the vehicle has
been sitting for eight hours or more with the engine off,
but this is used only as a reference. Let the engine
run at idle for ve minutes if outside temperatures are
50°F (10°C) or more. If it is colder than 50°F (10°C), you
may have to idle the engine longer. Should the uid
level be low during this cold check, you must check the
uid hot before adding uid. Checking the uid hot
will give you a more accurate reading of the uid level.
5-22