2003 GMC YUKON DENALI oil viscosity

If none of the above steps have made the light turn off,
have your dealer or qualified service center check
the vehicle. Your dealer has the proper test equipment
and diagnostic
tools to fix any mechanical or electrical
problems that may have developed.
€missions Inspection and Maintenance
Programs
Some state/provincial and local governments have or
may begin programs
to inspect the emission control
equipment on your vehicle. Failure to pass this
inspection could prevent you from getting a vehicle
registration.
Here are some things you need
to know to help your
vehicle pass an inspection:
Your vehicle will not pass this inspection
if the Check
Engine light is on or not working properly.
Your vehicle will not pass this inspection
if the OBD
(on-board diagnostic) system determines that critical
emission control systems have not been completely
diagnosed by the system. The vehicle would be
considered not ready for inspection. This can happen
if
you have recently replaced your battery or if your
battery has run down. The diagnostic system is
designed
to evaluate critical emission control systems
during normal driving. This may take several days
of routine driving.
If you have done this and your vehicle still does
not pass the inspection for lack of
OBD
system readiness, see your dealer or qualified service
center to prepare the vehicle for inspection.
Oil Pressure Gage
_I
United States Canada
The oil pressure gage shows the engine oil pressure in
psi (pounds per square inch) when the engine is
running. Canadian vehicles indicate pressure in kPa
(kilopascals).
Oil pressure may vary with engine speed, outside
temperature and
oil viscosity, but readings above the
low pressure zone indicate the normal operating range.
3-40

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
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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 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

Part D: Recommended Fluids and
Lubricants
Flyids and lubricants identified below by mme,
part number or specification may be obtained from
your dealer.
Usage
Engine Oil
Engine Coolant
Hydraulic Brake
System
Windshield
Washer Solvent
Fluid/Lubricant
Engine oil with the American
Petroleum Institute Certified for
Gasoline Engines starburst symbol
of the proper viscosity. To determine
the preferred viscosity for your
vehicle's engine, see Engine
Oil on
page
5- 13.
50/50 mixture of clean, drinkable
water and use only
DEX-COOL@Coolant. See Engine
Coolant on page
5-22.
Delco Supreme 1 l@ Brake Fluid or
equivalent
DOT-3 brake fluid.
GM Optikleen@Washer Solvent or
equivalent.
Usage
Power Steering System
Automatic
Transmission
Key Lock
Cylinders
Chassis
Lubrication
Front and
Rear Axle
Transfer Case
Fluid/Lubricant
GM Power Steering Fluid (GM Part No.
U.S. 1052884, in Canada
993294, or equivalent).
DEXRON@-Ill Automatic
Transmission Fluid.
Mulit-Purpose Lubricant, Superlube
(GM Part No.
U.S. 12346241 , in
Canada 10953474, or equivalent).
Chassis Lubricant (GM Part No.
U.S. 12377985, in Canada
88901242, or equivalent) or lubricant
meeting requirements of NLGl
#2,
Category LB or GC-LB.
SAE 75W-90 Synthetic Axle Lubricant (GM Part
No. U.S.
12378261, in Canada 10953455) or
equivalent meeting GM Specification
99861
15.
DEXRON@-Ill Automatic
Transmission Fluid.
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