check engine CHEVROLET SUBURBAN 1995 Owner's Manual

Checking Things Under the Hood
Hood Release
To open the hood, first
pull the handle inside
the vehicle.
Then go to the front
of
the vehicle and pull up
on the secondary hood
release, located just
to
the passenger side of
the center
of the grill.
Lift the hood.
Your vehicle, if it has
air conditioning, may
have
a auxiliary
engine fan in addition
to the belt driven fan.
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Before closing the hood, be sure all filler caps are on properly. Pull down
the hood and close it firmly.
Cleaning Your Diesel Engine
NOTICE:
If you spray or pour water or any other liquid on your engine
when it is warm or hot, or when
it is running, you could cause
serious damage
to it. If you ever clean the engine, clean it only
when it
is cold.
Engine Oil (Gasoline Engines)
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.
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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.
To Check 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.
When to Add Oil
If the oil is at or below the ADD mark, then you’ll 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 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.
Engine Oil (Diesel Engines)
It’s a good idea to check your engine oil level 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.
r 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.
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To Check Engine Oil
Pull out the dipstick and clean it with a paper towel or a cloth, then push it
back in all the way. Remove it again, keeping the tip down.
When to Add Oil
If the oil is at or below the ADD line, then you’ll 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 proper operating range, your engine
could be damaged.
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To remove the air cleaner filter on a gasoline engine or a 6.5 liter naturally
aspirated diesel engine, turn the wing nuts
to the left. Remove the cover and
change
the filter.
To remove the air cleaner filter on a 6.5 liter turbocharged diesel engine,
first remove the rubber elbow. Remember to observe the caution about
turbocharger blades
on the rubber elbow.
Then, unhook the cover retaining clips
and push the rear
of
the cover toward the
engine.
Automatic Transmission Nuid
When to Check and Change
A good time to check your automatic transmission fluid level is when the
engine
oil is changed. Refer to the Maintenance Schedule to determine
when to change your
fluid. 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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Wait at least 30 minutes before checking the transmission fluid level if you
have been driving:
0 When outside temperatures are above 90°F (32°C j,
At high speed for quite a while.
In heavy traffic - especially in hot weather.
0 While pulling a trailer.
To get the right reading, the fluid should be at normal operating
temperature, which
is 180°F to 200°F (82°C to 93°C).
To check transmission fluid hot: Get the vehicle warmed up by driving
about
15 miles (24 km) when outside temperatures are above 50°F (1 0°C).
If it's colder than 50°F (10"C), drive
the vehicle in DRIVE (D) until the
engine temperature gage moves and then remains steady for ten minutes.
Then follow the
hot check procedures.
To check transmission fluid cold: A cold check is made after the vehicle
has been sitting for eight hours
or more with the engine off and is used only
as
a reference. Let the engine run at idle for five minutes if outside
temperatures are 50°F (10°C) or more. If it's colder than 50°F (IO'C), you
may have to idle
the engine longer. Should the fluid level be low during a
cold check,
you must perform a hot check before adding fluid. This will
give you
a more accurate reading of the fluid level.
lo check the fluid hot or cold
0 Park your vehicle on a level place. Keep the engine running.
With the parking brake applied, place the shift lever in PARK (P).
With your foot on the brake pedal, move the shift lever through each
gear range, pausing
for about three seconds in each range. Then,
position
the shift lever in PARK (P).
Let the engine run at idle for three minutes or more.
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Then, without shutting off the engine, follow these steps:
1. Flip the handle up and then pull out the dipstick and wipe it with a
clean rag or paper towel.
2. Push it back in all the way, wait three seconds and then pull it back out
again.
3. Check both sides of the dipstick, and read the lower level. The fluid
level must be
in the COLD area for a cold check or in the HOT area or
cross-hatched area for a hot check.
4. If the fluid level is in the acceptable range, push the dipstick back in all
the way; then flip the handle down to lock the dipstick
in place.
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How to Add Fluid
Refer to the Maintenance Schedule to determine what kind of transmission
fluid to use. See “Recommended Fluids and Lubricants”
in the Index.
Add fluid only after checking the transmission fluid HOT.
(A COLD check
is used
only as a reference.) If the fluid level is low, add only enough of the
proper fluid to bring the level up to the HOT area for a
hot check. It doesn’t
take much fluid, generally less than a
int. Don 7 overfill. We recommend
you
use only fluid labeled DEXRON -111, because fluid with that label is
made especially for your automatic transmission. Damage caused by fluid
other than DEXRON@-111
is not covered by your new vehicle warranty.
8
After adding fluid, recheck the fluid level as described under “How to
Check.”
When the correct fluid level is obtained, push the dipstick back in all
the way; then flip
the handle down to lock the dipstick in place.
Manual Transmission Fluid
When to Check
A good time to have it checked is when the engine oil is changed. However,
the fluid
in your manual transmission doesn’t require changing.
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.
I 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.
Check the fluid level only when your engine is off, the vehicle is parked on
a level place and the transmission is cool enough for you to rest your fingers
on the transmission case.
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How to Check Lubricant
P
If the level is below the bottom of the filler plug hole, you’ll need to add
some lubricant.
If the differential is at operating temperature (warm), add enough lubricant
to raise the level to the bottom of the filler plug hole.
If the differential is cold, add enough lubricant to raise the level to 1/2 inch
(I 2 mm) below the filler plug hole.
What to Use
Refer to the Maintenance Schedule to determine what kind of lubricant to
use. See “Recommended Fluids and Lubricants” in the Index.
Engine Coolant
The following explains your cooling system and how to add coolant when it
is low. If you have a problem with engine overheating, see “Engine
Overheating”
in the Index.
The proper coolant for your vehicle will:
Give freezing protection down to -34°F (-37°C).
Give boiling protection up to 262°F (128°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning lights and gages work as they should.
What to Use
Use a mixture of one-half chi? wcmr (preferably distilled) and one-half
antifreeze that meets
“GM Specification 6038-M,” which won’t damage
aluminum parts.
You can also use a recycled coolant conforming to “GM
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