1994 CHEVROLET SUBURBAN Owners Manual

To remove the air
cleaner filter
on a gas
engine or
a 6.5 liter
naturally aspirated
diesel, 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, 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 Fluid
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 a
GM dealership 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.
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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, starting a fire. Be sure to get
an accurate reading if you check your transmission fluid.
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).
0 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 transmissionfluid hot: Get the vehicle warmed up by driving
about 15 miles
(24 km) when outside temperatures are above 50°F (IOOC).
If it’s colder than 50°F (IOOC), drive the vehicle in “D” (3rd Gear) until the
engine temperature gage moves and then remains steady for
ten minutes.
Then follow
the hot check procedures.
To check transmissionfluid 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 (IOOC), 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.
To check the fluid hot or cold
Park your vehicle on a level place.
e With the parking brake applied, place the shift lever in “P’ (Park).
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
“P” (Park).
Let the engine run at idle for three minutes or more.
Then, without shutting off the engine, follow these steps:
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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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WOW 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.
If the fluid level
is low, add only enough of the proper fluid to bring the
level up to the
COLD area for a cold check or the HOT area for a hot check.
It doesn’t take much fluid, generally
less than a pint. Don’t overfill. We
recommend you use
only fluid labeled DEXRON@-I11 or DEXRON@-IIE,
because fluids with that label are made especially for your automatic
transmission. Damage caused
by fluid other than DEXRON@-I11 or
DEXRON@-IIE is not covered
by your new vehicle warranty.
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 a
GM dealership Service Department.
If you do it yourself, be sure to follow all the instructions here, or you could
get
a false reading.
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, 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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Then, follow these steps:
1. Remove the filler plug.
2. Check that the lubricant level is up to the bottom of the filler plug hole.
3. If the fluid level is good, install the plug and be sure it is fully seated. If
the fluid level is low, add more fluid as described in the next steps.
How to Add Fluid
Here’s how to add fluid. Refer to the Maintenance Schedule to determine
what kind
of fluid to use. See “Recommended Fluids and Lubricants” in the
Index.
1. Remove the filler plug.
2. Add fluid at the filler plug hole. Add only enough fluid to bring the
fluid level up to the bottom of the filler plug hole.
3. Install the filler plug. Be sure the plug is fully seated.
Hydraulic Clutch
The hydraulic clutch in your vehicle is self-adjusting. A slight amount of
play (1/4 inch to 1/2 inch) in the pedal is normal.
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When to Check and What to Use
Refer to the
Maintenance Schedule
to determine how
often you should
check the fluid
level
in your clutch master
cylinder reservoir and
for the proper fluid.
See “Owner Checks and Services” and “Recommended Fluids and
Lubricants’’
in the Index.
How to check
The proper fluid should be added if the level does not reach the bottom of
the diaphragm when it’s
in place in the reservoir. See the instructions on the
reservoir cap.
Rear Axle
When to Checkand Change Lubricant
Refer to the Maintenance Schedule to determine how often to check the
lubricant and when to change it. See “Scheduled Maintenance Services” in
the Index.
How to Check Lubricant
If the level is below
the bottom
of the filler
plug hole,
you’ll need
to add some lubricant.
Add enough lubricant
to raise the level
to the
bottom
of the filler
plug hole.
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Whai to Use
Refer to the Maintenance Schedule to determine what kind of lubricant to
use. See “Recommended Fluids and Lubricants” in the Index.
Four- Wheel Drive
Most lubricant checks in this section also apply to four-wheel-drive
vehicles. However, they have two additional systems that need lubrication.
Transfer Case
When to Check Lubricant
Refer to the Maintenance Schedule to determine how often to check the
lubricant.
See “Periodic Maintenance Inspections” in the Index.
How to Check Lubricant
What to Use
If the level is below
the bottom of the filler
plug hole, you’ll
need
to add some lubricant.
Add enough lubricant
to raise the level to
the
bottom of the filler
plug hole.
Refer to the Maintenance Schedule
to determine what kind of lubricant to
use. See “Recommended Fluids and Lubricants” in the Index.
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Front Axle
When to Check and Change Lubricant
Refer to the Maintenance Schedule to determine how often to check the
lubricant and when to change
it. See “Scheduled Maintenance Services” in
the Index.
How to Check Lubricant
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
(12 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 -20°F (-29”C), or -34°F (-37°C) in
Give boiling protection up to 258°F (1 25°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Canada
and for vehicles with the cold climate option.
Let the warning lights and gages work as they should.
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