2003 CHEVROLET SILVERADO oil viscosity

Emissions 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, your GM dealer can prepare the
vehicle for inspection.
Oil Pressure Gage
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.United States
Canada
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What Kind of Engine Oil to Use
Oils recommended for your vehicle can be identi®ed by
looking for the starburst symbol.
This symbol indicates that the oil has been certi®ed 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 certi®ed
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 identi®ed as
SAE 5W-30. If you cannot ®nd 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 0ÉF (-18ÉC)
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 Certi®ed For Gasoline Engines
starburst symbol. Failure to use the recommended
oil can result in engine damage not covered by
your warranty.
GM Goodwrench
žoil meets all the requirements for
your vehicle.
If you are in an area of extreme cold, where the
temperature falls below-20ÉF (-29ÉC), it is
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 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 light 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 and ®lter 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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Part D: Recommended Fluids and
Lubricants
Fluids and lubricants identi®ed below by name, part
number or speci®cation may be obtained from your
dealer.
Usage Fluid/Lubricant
Engine OilEngine oil with the American
Petroleum Institute Certi®ed for
Gasoline Engines starburst symbol
of the proper viscosity. To determine
the preferred viscosity for your
vehicle's engine, see
Engine Oil on
page 5-16.
Engine Coolant50/50 mixture of clean, drinkable
water and use only
DEX-COOL
žCoolant. SeeEngine
Coolant on page 5-30.
Hydraulic Brake
SystemDelco Supreme 11 Brake Fluid or
equivalent DOT-3 brake ¯uid.
Windshield
Washer SolventGM Optikleen
žWasher Solvent or
equivalent.
Usage Fluid/Lubricant
Hydraulic
Clutch System
(5±Speed
Trans.)Hydraulic Clutch Fluid (GM Part No.
U.S. 12345347, in Canada
10953517, or equivalent DOT-3
brake ¯uid).
Hydraulic
Clutch System
(6±Speed
Trans.)Hydraulic Clutch Fluid. Use only GM
Part No. U.S. 88958860, in Canada
88901244.
Power Steering
SystemGM Power Steering Fluid (GM Part
No. U.S. 1052884, in Canada
993294, or equivalent).
Manual
Transmission
(5±Speed with
Low Gear,
RPO MW3)GM Goodwrench Synthetic Manual
Transmission Fluid (GM Part No.
U.S. 12346190, in Canada
10953477) or equivalent SAE
75W-85 GL-4 gear oil.
Manual
Transmission
(5±Speed
without Low
Gear, RPO
MG5)Synchromesh Transmission Fluid
(GM Part No. U.S. 12345349, in
Canada 10953465, or equivalent).
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