Page 233 of 372

If your vehicle has a 7.4L engine and air conditioning,
your vehicle will have a auxiliary engine fan
in addition
to the belt driven
fdn.
If your vehicle has air conditioning, the auxiliary
engine fan under the hood can start up and
injure you even when the engine is not running.
Keep hands, clothing and tools away from any
underhood electric fan.
~ Things that burn can get on hot engine parts and
start a
fire. These include liquids like gasoline,
~ 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. Before closing
the hood, be sure
all the filler caps are
on properly.
Then
lift the hood to relieve pressure on the hood prop.
Remove the hood prop from the slot
in the hood and
return the prop to
its retainer. Then just let the hood
down and close
it firmly.
Noise Control System
The following information relates to compliance with
Federal noise emission standards for vehicles with a
Gross Vehicle Weight Rating (GVWR) of more than
10,000 lbs. (4 536 kg). The Maintenance Schedule
booklet provides information on maintaining the noise
control system to minimize degradation of the noise
emission control system during the life of your vehicle.
The noise control system warranty is given
in your
Warranty booklet.
These standards apply only
to vehicles sold in the
United States.
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Tampering With Noise Control
System Prohibited
Federal law prohibits the following acts or the
causing thereof:
1. The removal or rendering inoperative by any person,
other than for purposes of maint,enance, repair or
replacement, of any device
01- element of design
incorporated into any new vehicle
for the purpose of
noise control, prior to its sale or delivery to the
ultimate purclwser
or while it is in use; or
2. The use of the vehicle after SLIC~ device or element
of design has been removed or rendered inoperative
by any person.
Among those acts presumed to constitute tampering are
the acts listed below.
insulation:
0 Removal of noise shields or underhood insulation.
Engine:
Removal or rendering engine speed governor (if so
equipped) inoperative so as to allow engine speed to
exceed manufrtctureer specifications.
Fan and Drive:
Removal of fan clutch (if so equipped) or rendering
clutch inoperative.
0 Removal of fan shroud (if so equipped).
Air Intake:
0 Reversing air cleaner cover.
Exhaust:
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Page 235 of 372

Engine Oil (Gasoline Engine)
If your vehicle has a diesel engine, see “Engine Oil
(Diesel Engine)” in the Diesel Engine Supplement.
It‘s
a good idea to check your engine oil every time you
be warm and the vehicle must be on level ground.
c‘ Get fuel. In order to get an accurate reading, the oil must
Turn
off the engine and give
the oil
a few minutes to drain
back into the
oil pan. If you
don’t, the oil dipstick might
not show the actual level.
Checking Engine Oil
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.
When to Add Oil
If the oil is at or below the ADD mark, then ~011’11 need to
add some oil. But you must use the right kind. This part
explains what kind
of oil to use. For crankcase capacity,
see “Capacities and Specifications”
in the Index.
NOTICE:
Don’t add too much oil. If your engine has so much
oil that the oil level gets above the upper mark that
shows the proper operating range, your engine could be damaged.
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What Kind of Oil to Use
The engine oil filler cap is located between the air
cleaner and engine oil dipstick.
Just
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. 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 change your own oil,
be sure you use
oil that 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 following chart:
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RECOMMENDED SAE VISCOSITY GRADE ENGINE OILS
FOR BEST FUEL ECONOMY AND COLD STARTING, SELECT THE LOWEST
SAE VISCOSITY GRADE
OIL FOR THE EXPECTED TEMPERATURE RANGE.
HOT
WEATHER
i +38
1 +27
LOOK
FOR THIS
SYMBOL
COLD
WEATHER
DO NOT USE SAE 2OW-50 OR ANY OTHER GRADE OIL NOT RECOMMENDED
As shown in the chart, SAE 5W-30 is best for your
vehicle. However, you can use
SAE ]OW-30 if it’s going
to be
0°F (- 18°C) or above. These numbers on an oil
container
show its viscosity, or thickness. Do not use
other viscosity oils, such as
SAE 20W-50.
NOTICE:
Use only engine oil with the American Petroleum
Institute Certified For Gasoline Engines
LcStarbur~t” 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.
Engine Oil Additives
Don‘t add anything to your oil. Your GM dealer is ready
to advise
if you think something should be added.
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When to Change Engine Oil
See if any one of these is true for you:
0
0
0
0
0
Most trips are less than 5 to 10 miles (8 to 16 km).
This is particularly important when outside
temperatures are below freezing.
Most trips include extensive idling (such
as frequent
driving
in stop-and-go traffic).
Most trips are through dusty areas.
You frequently tow a trailer or use a carrier on top of
your vehicle.
The vehicle
is used for delivery service, police, taxi
or other commercial application.
Driving under these conditions causes engine oil to
break down sooner. If any one of these is true for your
vehicle, then you need to change your oil and filter
every
3,000 miles (5 000 km) or 3 months -- whichever
occurs first.
If none of them is true, change the oil and filter every
7,500 miles (1 2 SO0 km) or 12 months -- whichever
occurs first. Driving a vehicle
with a fully warnled
engine under highway conditions causes engine oil to
break down slower.
What to Do with Used Oil
Did you know that 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 throw
away 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 real threat to the environment. If you
change your own
oil, be sure to drain all free-flowing oil
from the filter before disposal. Don't ever 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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Page 239 of 372

Air Cleaner Refer to the Maintenance Schedule to determine when to
replace the air filter and crankcase ventilation filter.
See “Scheduled Maintenance Services’‘
in the Index.
. . ,.?
To remove the air cleaner filter:
loosen screw bolt to air induct hose
0 remove the three bolts
remove the f~dl air cleaner housing
unsnap the three clips
Then
tilt the top cover up and back to expose the filter
element. Install
a new filter element with the folds in the
down position.
See “Normal Replacement Parts” for the proper filter
to use.
b
Operating the engine with the air cleaner off can
cause you or others to be burned. The air cleaner
not only cleans the
air, it stops flame if the engine
backfires.
If it isn’t there, and the engine
backfires, you could be burned. Don’t drive with
it
off, and be careful working on the engine with
the
air cleaner off.
1 NOTICE:
If the air cleaner is off, a backfire can cause a
damaging engine fire. And, dirt can easily get
into your engine, which will damage it. Always
have the
air cleaner in place when you’re driving.
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Automatic Transmission Fluid
7 ’ ~ n to Check and Change
A good time to check your automatic transmission fluid
level is when the engine oil is changed.
Change
both the fluid and filter 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:
0 In heavy city traffic where the outside temperature
0 In hilly or mountainous terrain.
0 When doing frequent trailer towing.
regularly
reaches
90°F (32°C) or higher.
0 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, the
fluid and filter do not require changing.
See “Scheduled Maintenance Services”
in the Index.
How to Check
Because this operation can be a little difficult, you
may choose to have this done at your GM dealer
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 little fluid can damage your
transmission.
Too much can mean that some of
the fluid could come out and fall on hot engine parts or exhaust system parts, starting a fire. Be
sure to get an accurate reading if you check your
transmission fluid.
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