Page 157 of 384

Oil Pressure Gage
The engine oil pressure
gage, on the lower right
portion of your instrument
panel cluster, shows
engine oil pressure in
psi (pounds per square
inch) or in kPa
(kilopascals).
Oil pressure may vary with outside temperature and oil
viscosity, but readings of 30 to 40 psi (205 to 275 kPa)
on gasoline engines at operating temperature and
moderate road speeds are normal. If you have a diesel
engine, the normal operating range should be between
35 and 70 psi (240 to 480 kPa).A reading in the low pressure zone may be caused by a
dangerously low oil level or other problem.
If you have a Caterpillar®diesel engine, also see your
Caterpillar®Operation & Maintenance Manual.
{CAUTION:
Do not keep driving if the oil pressure is low.
If you do, your engine can become so hot that
it catches re. You or others could be burned.
Check your oil as soon as possible and have
your vehicle serviced.
Notice:Lack of proper engine oil maintenance
may damage the engine. The repairs would not be
covered by your warranty. Always follow the
maintenance schedule in this manual for changing
engine oil.
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What Kind of Engine Oil to UseLook for three things:
•GM6094M
Your vehicle’s engine requires oil meeting GM
Standard GM6094M. Look for and use only an oil
that meets GM Standard GM6094M.
•SAE 5W-30
As shown in the viscosity chart, SAE 5W-30 is best
for your vehicle.
These numbers on an oil container show its
viscosity, or thickness. Do not use other viscosity
oils such as SAE 20W-50.
•American Petroleum Institute (API) starburst symbol
Oils meeting these
requirements should have
the starburst symbol on
the container. This symbol
indicates that the oil
has been certified by the
American Petroleum
Institute (API).
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Page 235 of 384

•SAE 15W-40
As shown in the viscosity chart, SAE 15W-40 is best
for your vehicle. When it is very cold, below 0°F
(−18°C), you should use SAE 5W-40 to improve cold
starting.
These numbers on the oil container show its
viscosity, or thickness. Do not use other viscosity
oils such as SAE 10W-30, SAE 10W-40, or
SAE 20W-50.
This doughnut-shaped
logo (symbol) is used on
most oil containers to help
you select the correct oil. It
means that the oil has been
certified by the American
Petroleum Institute.
Look for this on the oil container, and use only those
oils that display this logo.Engine Oil Additives
Do not add anything to the oil. The recommended oils
with the API service symbol are all you need for good
performance and engine protection.
When to Change Engine Oil (Vehicles
Without the Engine Oil Life System)
Change the engine oil and filter every 15,000 miles
(24 000 km), or every 12 months, or every 750 hours of
engine operation, whichever occurs first. See
Scheduled Maintenance on page 6-5.
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Page 239 of 384

•SAE 10W-40 or SAE 15W-40
As shown in the viscosity chart, SAE 10W-40 or
SAE 15W-40 is best for your vehicle. When it is very
cold, below 0°F (−18°C), you should use SAE 5W-40
to improve cold starting.
These numbers on the oil container show its
viscosity, or thickness. Do not use other viscosity
oils such as SAE 10W-30 or SAE 20W-50.
This doughnut-shaped
logo (symbol) is used on
most oil containers to
help you select the correct
oil. It means that the oil
has been certified by
the American Petroleum
Institute.
Look for this on the oil container, and use only those
oils that display this logo.Engine Oil Additives
Do not add anything to the oil. The recommended oils
with the API service symbol are all you need for
good performance and engine protection.
When to Change Engine Oil (Vehicles
Without the Engine Oil Life System)
Change the engine oil and filter every 15,000 miles
(24 000 km), or every 12 months, or every 750 hours of
engine operation, whichever occurs first. If the vehicle
is used primarily for long trip, highway service, change
the engine oil and filter every 18,000 miles (28 800 km),
or every 12 months, or every 750 hours of engine
operation, whichever occurs first. SeeScheduled
Maintenance on page 6-5.
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Page 355 of 384

Part C: Recommended Fluids and
Lubricants
Fluids and lubricants identified below by name, part
number, or specification can be obtained from your
dealer/retailer.
Usage Fluid/Lubricant
Engine Oil
(Gasoline
Engine)Engine oil which meets
GM Standard GM6094M and
displays the American Petroleum
Institute (API) Certified for Gasoline
Engines starburst symbol. To
determine the proper viscosity for
your vehicle’s engine, see “Engine
Oil” in the Index.
Engine Oil
(DURAMAX
®/
Isuzu Diesel
Engines)Engine oils with the letters CJ-4 are
required for your vehicle. The CJ-4
designation can appear either alone
or in combination with other
American Petroleum Institute (API)
designations, such as API CJ-4/SL.
These letters show API levels of
quality. To determine the preferred
viscosity for your vehicle’s diesel
engine, see “Engine Oil” in the Index.
Engine Oil
(Caterpillar
®
Diesel Engine)See the Caterpillar
®Operation &
Maintenance Manual for engine oil
recommendations.
Usage Fluid/Lubricant
Engine Coolant
(Caterpillar
®
Diesel Engine)See the Caterpillar
®Operation &
Maintenance Manual for engine
coolant recommendations.
Engine Coolant
(Gasoline
Engine &
DURAMAX
®/
Isuzu Diesel
Engines)50/50 mixture of clean, drinkable
water and use only DEX-COOL
®
Coolant. SeeEngine Coolant
(Caterpillar®Diesel Engines) on
page 5-44orEngine Coolant
(Gas and DURAMAX
®/Isuzu 7.8L
L6 Engines) on page 5-44.
Hydraulic Brake
SystemDelco
®Supreme 11 Brake Fluid or
equivalent DOT-3 brake fluid.
Windshield
Washer SolventOptikleen
®Washer Solvent.
Clutch Bearing
LubricantClutch Bearing Lubricant
(GM Part No. 12378484 or
equivalent NLGI #3 consistency).
Exhaust Brake
Ball Joint Cap
LubricantHigh-Temperature Grease
(GM Part No. U.S. 1051344, in
Canada 903037) or NLGI #3
consistency.
Power Steering
SystemDEXRON
®-VI Automatic
Transmission Fluid.
Manual
TransmissionSynthetic Manual Transmission Fluid
(GM Part No. U.S. 88861952, in
Canada 88861953).
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