2003 GMC YUKON DENALI Owners Manual

While refueling, hang the fuel cap by the tether using
the
hook located on the inside of the filler door.
If you get fuel on yourself and then something
ignites it, you could be badly burned. Fuel can
spray out on you
if you open the fuel cap too
quickly. This spray can happen if your tank is
nearly full, and
is more likely in hot weather.
Open the fuel cap slowly and wait for any “hiss” noise to
stop. Then unscrew the cap all
the way.
Be careful not
to spill fuel. Clean fuel from painted
surfaces as soon
as possible. See Cleaning the Outside
of Your Vehicle on page 5-81.
To remove the fuel cap, turn it slowly to the left
(counterclockwise).
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When you put the fuel cap back on, turn it to the right
(clockwise) until you hear a clicking sound. Make
sure you fully install the cap. The diagnostic system can
determine
if the fuel cap has been left off or improperly
installed. this would allow fuel
to evaporate into the
atmosphere. See Malfunction
indicator Lamp on
page 3-38.
Notice: If you need a new fuel cap, be sure to get
the right type. Your dealer can get one for you.
If you get the wrong type, it may not fit properly.
This may cause your malfunction indicator lamp to
light and may damage your fuel tank and emissions
system. See “Malfunction Indicator Lamp”
in the
Index.
Cillinc a Dortable Fun’ Container
~~ ~
Never fill a portable fuel container while it is in
your vehicle. Static electricity discharge from
the container can ignite
the gasoline vapor.
You can
be badly burned and your vehicle
damaged
if this occurs. To help avoid injury to
you and others:
Dispense gasoline only into approved
containers.
@ Do not fill a container while it is inside a
vehicle, in a vehicle’s trunk, pickup bed or on any surface other than the ground.
@ Bring the fill nozzle in contact with the
inside of the fill opening before operating
the nozzle. Contact should be maintained until the filling is complete.
Don’t smoke while pumping gasoline.
5-9

Checking Things Under
the
Hood
- .lings It burn can get c hot engine parts
and start a fire. These include liquids like fuel,
oil, coolant, brake fluid, windshield washer and
other fluids, 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.
Hood Release
To open the hood, do the following:
1. Pull the handle located
inside the vehicle
to
the lower left of
the steering wheel.
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2. Then go to the front of the vehicle and pull up on
the secondary hood release, located near the
center of the grill.
3. Lift the hood,
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Engine Compartment Overview
When you open the hood on the VORTECTM 6000 V8 engine you will see the following:
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A. Engine Air CleanedFilter
B. Coolant Surge Tank
C. Air Filter Restriction Indicator
D. Engine Qii Dipstick
E. Engine Oil Fill
F. Automatic Transmission Dipstick
G. Fan
H. Remote Negative (-) Terminal (GND)
I. Remote Positive (+) Terminal
J. Power Steering Fluid Reservoir (Out of View)
K. Brake Master Cylinder Reservoir
L. Underhood Fuse Block
M. Battery
N. Windshield Washer Fluid Reservoir
Before closing the hood, be sure all filler caps are on
properly. Pull down the hood and close
it firmly.
Engine Oil
If the CHECK OIL LEVEL message appears on the
instrument cluster, it means you need to check
your engine oil level right away.
For more information, see “CHECK OIL LEVEL” under
DIC Warnings and Messages on page 3-52.
You should check your engine oil level regularly; this is
an added reminder.
Checking Engine Oil
It’s a good idea to check your 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 has a yellow loop handle and
is located in the engine
compartment on the
passenger’s side of the
vehicle. See Engine
Compartment Overview on
page
5- 12 for more
information on location.
Turn
off the engine and give the oil several minutes to
drain back into the oil pan. If you don’t, the oil
dipstick might not show the actual level.
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.
5-1 3

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, see Capacities and Specifications on
page
5-96.
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 oil fill cap is
located on the valve cover
on the passenger's side
of the vehicle. See Engine
Compartment Overview
on page
5-12 for further
~ location information.
Be sure to
fill it enough to put the level somewhere in
the proper operating range. Push the dipstick all the way
back in when you're through.
5-1 4

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.
1-1 If you choose to perform
i* Y
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
I I Petroleum Institute certified
for gasoline engines.
fou should also use the proper viscosity oil for your
vehicle, as shown in the viscosity chart.
RECOMMENDED SAE VISCOSITY GRADE ENGINE OILS
HOT
WEATHER
-
"F
5.100
+ 80
+ 60
t 40
t 20
0
f
-
"C
- +3e
- t 2i
- + 1t
- t4
- -7
- - 16

I
I
i
I-
/
COLD
WEATHER
DO NOT USE SAE 1OW-40, SAE 2OW-50 OR ANY OTHER VISCOSITY GRADE OIL NOT RECOMMENDED
5-1 5