2003 GMC YUKON DENALI Owners Manual

As in the chart shown previously, SAE 5W-30 is the
only viscosity grade recommended for your vehicle. You
should look for and use only oils which have the API
Starburst symbol and which are also identified as
SAE 5W-30. If you cannot find such SAE 5W-30 oils,
you can use an SAE 1OW-30 oil which has the API
Starburst symbol,
if it's going to be 0°F (-18°C)
or above.
Do not use other viscosity grade oils, such as
SAE 1OW-40 or SAE 20W-50 under any conditions.
Notice: Use only engine oil with the American
Petroleum Institute Certified For Gasoline Engines
starburst symbol. Failure to use the recommended
oil can result in engine damage not covered by
your warranty.
GM Goodwrench@ oil meets all the requirements for
your vehicle.
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 OW-30 oil. Both will provide
easier cold starting and better protection for your engine
at extremely low temperatures.
Engine Oil Additives
Don't add anything to your oil. The recommended oils
with the starburst symbol are all you will need for
good performance and engine protection.
When to Change Engine Oil (GM Oil
Life System)
Your vehicle has a computer system that lets you know
when to change the engine oil and filter. 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 message will
come on. Change your oil as soon as possible within
the next two times you stop for fuel. It is possible that,
if
you are driving under the best conditions, the oil life
system may not indicate that an oil change is necessarv
for over a year. However, your engine oil and filter
must be changed at least once a year and at this time
the system must be reset. It is also important
to
check your oil regularly and keep it at the proper level.
If the system is ever reset accidentally, you must
change your 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.
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6

How to Reset the CHANGE ENGINE OIL
Message
The GM Oil Life System calculates when to change
your engine oil and filter based on vehic!e
use. Anytime
your oil is changed, reset the system
so it can
calculate when the next oil change is required.
If a
situation occurs where you change your
oil prior to a
CHANGE ENGINE OIL message being turned on, reset
the system.
To reset the CHANGE ENGINE
OIL message, see “GM
Oil Life System” under DIC Operation and Displays
on page 3-43 for vehicles equipped with the DIC, or do
the following:
1. Turn the ignition key to RUN with the engine off.
2. Fully press and release the accelerator pedal three
If the OIL LIFE RESET message flashes for
10 seconds,
the system is reset.
If the system does not reset, try the procedure once
again. If it still does not reset, see your dealer for
service. times
within five seconds.
What to Do with Used Oil
Used engine oil contains certain elements that may be
unhealthy for your skin and could even cause cancer.
Don’t 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
filter 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 your used oil, ask
your dealer, a service station or a local recycling center
for help.
Engine Air Cleaner/Filter
The engine air cleanedfilter assembly has an air filter
restriction indicator that lets you know when the engine
air cleaner/filter is dirty and needs to be serviced.
The air filter restriction indicator is located on the air
filter assembly cover. See Engine Compartment
Overview
on page 5-72 for more information on location.
See Part
B: Owner Checks and Services on page 6-10
to determine when to check the air filter restriction
indicator.
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The service window (A)
with the percentage scale shows the amount of
engine air cleaner/filter life used.
I I
When both service window (A) and service window (B)
turn orange, replace the engine air cleanedfilter.
After changing the engine air cleaner/filter, press the
button on top of the air filter restriction indicator
to
reset it. Your
engine air cleaner/filter is located in the air filter
housing near the front corner of the engine compartment
on the passenger’s side of the vehicle. See Engine
Compartment Overview
on page 5-12 for more
information on location.
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I
1. To remove the engine air cleaner/filter, loosen the
screws on the cover.
2. Lift the cover upward and remove the engine air
cleaner/filter
out of the air cleaner housing. Care
should be taken to dislodge as little dirt as possible.
3. Clean the filter sealing surface and the housing.
4. Install the new engine air cleanedfilter. Refer
to the Maintenance Schedule to determine when
to replace the engine air cleanedfilter. See
Part 5:
Owner Checks and Services on page 6- 10.
Operating L.L engine _____. the air cleaner/filter
off can cause you or others to be burned. The
air cleaner not only cleans the air,
it stops
flame if the engine backfires.
If it isn’t there
and the engine backfires, you could be burned. Don’t drive with
it off, and be careful working
on the engine with the air cleanedfilter
off.
Notice: If the air cieaner/filter is off, a backfire can
cause a damaging engine fire. And, dirt can
easily get into your engine, which will damage
it.
Always have the air cleanedfilter in place when
you’re driving.
5. Install the cover and tighten the screws.
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Automatic Transmission Fluid
When to Check and Change
A good time to check your automatic transmission fluid
level is when the engine oil is changed.
Change both the fluid and filter every
50,000 miles
(83
000 km) if the vehicle’s GVWR is over 8,600 or 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.
0 In hilly or mountainous terrain.
When doing frequent trailer towing.
Uses such as found in taxi, police or delivery
service.
If your vehicle’s GVWR is not over 8,600 and you do
not use your vehicle under any of these conditions,
change the fluid and filter every
100,000 miles
(1 66 000 km).
How to Check
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.
Notice: Too much or too little fluid can damage
your transmission. Too much can mean that some of the fluid could come out and fall
on hot engine
part or exhaust system parts, starting a fire.
Too little fluid could cause the transmission to
overheat. Be sure to get an accurate reading if you
check your transmission fluid.
Wait at least 30 minutes before checking the
transmission fluid 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.
See
Part A: Scheduled Maintenance Services on
page 6-4.
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To get the right reading, the fluid 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's colder than 50°F
(IO'C), drive the vehicle
in THIRD
(3) until the engine temperature gage
moves and then remains steady for
10 minutes.
A cold fluid 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 five minutes
if outside temperatures are
50°F (10°C) or more.
If it's colder than 50°F (IO'C), you
may have to idle the engine longer. Should the fluid
level be low during this cold check,
you must check the
fluid hot before adding fluid. Checking the fluid hot
will give you a more accurate reading of the fluid level.
Checking the Fluid Level
Prepare your vehicle as follows:
@ Park your vehicle on a level place. Keep the engine
running.
With the parking brake applied, place the shift lever
in PARK (P).
With your foot on the brake pedal, move the shift
lever through each gear range, pausing for about
three seconds in each range. Then, position the shift
lever in
PARK (P).
@ Let the engine run at idle for three minutes or more.
Then, without shutting
off the engine, follow
these steps:
1- The transmission dipstick handle with the graphic is
located at the rear of
the engine compartment,
on the passenger's side.
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See Engine Compartment Overview on page 5-12 for
more information on location.
1. Flip the handle up and then pull out the dipstick
and wipe it with a clean rag or paper towel.
2. Push it back in all the way, wait three seconds and
then pull it back out again.
3. Check both sides of the dipstick, and read the lower
level. The fluid level must be in the COLD area,
below the cross-hatched area, for a cold check or in
the HOT area or cross-hatched area for a
hot check.
4. If the fluid level is in the acceptable range, push the
dipstick back in all the way; then flip the handle
down
to lock the dipstick in place.
How to Add Fluid
Refer to the Maintenance Schedule to determine what
kind of transmission fluid
to use. See Part D:
Recommended Fluids and Lubricants on page 6-15.
Add fluid only after checking the transmission fluid while
it is hot. (A cold check is used only as
a reference.) If
the fluid level is low, add only enough of the proper fluid
to bring the level up to the HOT area for a hot check.
It doesn't take much fluid, generally less than one
pint (0.5 L). Don't overfill.
Notice: We recommend you use only fluid labeled
DEXRON@
-111, because fluid with that label is
made especially for your automatic transmission.
Damage caused by fluid other than DEXRON@
-111 is
not covered by your new vehicle warranty.
After adding fluid, recheck the fluid level as
described under How to Check.
When the correct fluid level is obtained, push the
dipstick back in all the way; then flip the handle
down
to lock the dipstick in place.
Engine Coolant
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.
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The following explains your cooling system and how to
add coolant when it is low. If you have a problem
with engine overheating, see Engine Overheating
on
page 5-25.
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.
e Let the warning lights and gages work as they
should.
Notice: When adding coolant, it is important that
you use only
DEX-COOL@ (silicate-free) coolant.
If coolant other than DEX-COOL@ is added to the
system, premature engine, heater core or radiator
corrosion may result. In addition, the engine coolant
will require change sooner
-- at 30,000 miles
(50,000 km) or 24 months, whichever occurs first.
Damage caused by the use of coolant other than
DEX-COQL.@ is not covered by your new vehicle
warranty.
What to Use
Use a mixture of one-half clean, drinkable water and
one-half DEX-COOL@ coolant which won’t damage
aluminum parts.
!f YOU uss this coolant mixture,
you don’t need
to add anything else.
Adding c..ly
c 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 wouldn’t get the overheat warning.
Your engine could catch fire and you or others
could be burned. Use a
50/50 mixture of clean,
drinkable water and DEX-COQL@ coolant.
Notice: If you use an improper coolant mixture,
your engine could overheat and be badly damaged.
The repair cost wouldn’t 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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