GMC YUKON 2003 Owner's Manual

When to Add Engine Oil
If the oil is at or below the cross-hatched area at the tip
of the dipstick, then you’ll need to add at least one
quart of oil. But you must use the right kind. This part
explains what kind of oil to use. For engine oil crankcase
capacity, seeCapacities and Specifications on
page 5-106.
Notice:Don’t add too much oil. If your engine has
so much oil that the oil level gets above the
cross-hatched area that shows the proper operating
range, your engine could be damaged.The engine oilfill cap for
the VORTEC™4800,
5300, 6000 and 8100 V8
engine is located on
the engine valve cover, on
the passenger’s side of
the vehicle.
Your vehicle may have a cap with text and a graphic, or
just a graphic as shown. SeeEngine Compartment
Overview on page 5-12for more information on location.
Be sure tofill it enough to put the level somewhere in
the proper operating range. Push the dipstick all the way
back in when you’re through. All Other Engines
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What Kind of Engine Oil to Use
Oils recommended for your vehicle can be identified by
looking for the starburst symbol.
This symbol indicates that the oil has been certified by
the American Petroleum Institute (API). Do not use
any oil which does not carry this starburst symbol.
If you choose to perform
the engine oil change
service yourself, be sure
the oil you use has
the starburst symbol on
the front of the oil
container. If you have your
oil changed for you, be
sure the oil put into
your engine is American
Petroleum Institute certified
for gasoline engines.
You should also use the proper viscosity oil for your
vehicle, as shown in the viscosity chart.
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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 cannotfind such SAE 5W-30 oils,
you can use an SAE 10W-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 10W-40 or SAE 20W-50 under any conditions.
Notice:Use only engine oil with 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.
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),itis
recommended that you use either an SAE 5W-30
synthetic oil or an SAE 0W-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 andfilter. 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 necessary for over a year. However, your
engine oil andfilter must be changed at least once a year
and at this time the system must be reset. Your dealer
has GM-trained service people who will perform this work
using genuine GM parts and reset the system. 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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How to Reset the CHANGE ENGINE OIL
Message
The GM Oil Life System calculates when to change
your engine oil andfilter based on vehicle 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 can 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”underDIC Operation and Displays
on page 3-54for 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
times withinfive seconds.
If the OIL LIFE RESET messageflashes 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.
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.
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Engine Air Cleaner/Filter
SeeEngine Compartment
Overview on page 5-12for
location of engine air
cleaner/filter and change
indicator (if equipped).
When to Inspect
If your vehicle is equipped with afilter change indicator
it lets you know when thefilter needs to be replaced.
Inspect the air cleaner/filter change indicator every
15,000 miles (25 000 km) and replace thefilter if
necessary. Vehicles without a change indicator inspect
the air cleaner/filter every 15,000 miles (25 000 km)
and replace thefilter every 30,000 miles (50 000 km). If
you are driving in dusty/dirty conditions, inspect the
filter or change indicator at each engine oil change.
How to Inspect
Locate thefilter change indicator. When the change
indicator turns black or is in the red/orange“change”
zone, replace thefilter and reset the indicator. To
inspect the air cleaner/filter, remove thefilter from the
vehicle and lightly shakefilter to release loose dust and
dirt. If thefilter remains“caked”with dirt, a newfilter
is required.
To inspect and replace thefilter and reset the indicator
(if equipped), do the following:
The air cleaner/filter assembly is located on the front
corner of the engine compartment on the passenger’s
side of the vehicle.
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1. Loosen the screws on the cover of the housing and
lift up the cover.
2. Remove the air cleaner/filter from the housing. Care
should be taken to dislodge as little dirt as possible.
3. Clean thefilter sealing surface and the housing.
4. Install the new engine air cleaner/filter.
5. Reinstall the cover and tighten the screws.
{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
stopame if the engine backres. If it isn’t there
and the engine backres, you could be burned.
Don’t drive with it off, and be careful working on
the engine with the air cleaner/lter off.
Notice:If the air cleaner/lter is off, a backre can
cause a damaging enginere. And, dirt can
easily get into your engine, which will damage it.
Always have the air cleaner/lter in place when
you’re driving.
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Automatic Transmission Fluid
When to Check and Change
A good time to check your automatic transmissionfluid
level is when the engine oil is changed.
Change both thefluid andfilter 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.
•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 thefluid andfilter every 100,000 miles
(166 000 km).
SeePart A: Scheduled Maintenance Services on
page 6-4.
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 littleuid can damage
your transmission. Too much can mean that some
of theuid could come out and fall on hot engine
part or exhaust system parts, starting are.
Too littleuid could cause the transmission to
overheat. Be sure to get an accurate reading if you
check your transmissionuid.
Wait at least 30 minutes before checking the
transmissionfluid 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, thefluid should be at normal
operating temperature, which is 180°Fto200°F
(82°Cto93°C).
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Get the vehicle warmed up by driving about 15 miles
(24 km) when outside temperatures are above 50°F
(10°C).Ifit’s 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 coldfluid 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 forfive minutes if outside temperatures are
50°F (10°C) or more. If it’s colder than 50°F (10°C), you
may have to idle the engine longer. Should thefluid
level be low during this cold check, youmustcheck the
fluid hot before addingfluid. Checking thefluid hot
will give you a more accurate reading of thefluid 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:
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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SeeEngine Compartment Overview on page 5-12for
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. Thefluid 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 thefluid level is in the acceptable range, push the
dipstick back in all the way; thenflip the handle
down to lock the dipstick in place.How to Add Fluid
Refer to the Maintenance Schedule to determine what
kind of transmissionfluid to use. SeePart D:
Recommended Fluids and Lubricants on page 6-17.
Addfluid only after checking the transmissionfluid while
it is hot. (A cold check is used only as a reference.) If
thefluid level is low, add only enough of the properfluid
to bring the level up to the HOT area for a hot check.
It doesn’t take muchfluid, generally less than one
pint (0.5 L).Don’t overfill.
Notice:We recommend you use onlyuid labeled
DEXRON
®-III, becauseuid with that label is
made especially for your automatic transmission.
Damage caused byuid other than DEXRON
®-III is
not covered by your new vehicle warranty.
•After addingfluid, recheck thefluid level as
described underHow to Check.
•When the correctfluid level is obtained, push the
dipstick back in all the way; thenflip the handle
down to lock the dipstick in place.
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Engine Coolant
The cooling system in your vehicle isfilled 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 occursfirst, if you add only
DEX-COOL
®extended life coolant.
The following explains your cooling system and how to
add coolant when it is low. If you have a problem
with engine overheating, seeEngine Overheating on
page 5-29.
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.
•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 occursrst.
Damage caused by the use of coolant other
than DEX-COOL
®is not covered by your new vehicle
warranty.
What to Use
Use a mixture of one-halfclean, drinkable waterand
one-half DEX-COOL®coolant which won’t damage
aluminum parts. If you use this coolant mixture,
you don’t need to add anything else.
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