maintenance CHEVROLET SUBURBAN 1994 User Guide

Air Cleaner
Refer to the
Maintenance Schedule to determine when to
replace the air filter.
See “Scheduled
Maintenance Services” in the Index.
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 d\
amage it. Always have the air cleaner in place when you’re drivin\
g.
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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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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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How To Check Power Steering Fluid
l
Unscrew the cap and
wipe the dipstick with
a clean rag. Replace
the cap and
completely tighten it.
Then remove the cap
again and look
at the
fluid level on the
dipstick.
0 When the engine
compartment is
hot, the level
should
be at the
FULL mark.
When the engine
compartment is
cool, the
level
should be at the
FULL COLD
mark.
Whaf fo Add
Refer to the Maintenance Schedule to determine what kind of fluid to use.
See “Recommended Fluids and Lubricants” in the Index.
NOTICE:
When adding power steering fluid or making a complete fluid
change, always
use the proper fluid. Failure to use the proper
fluid can cause leaks and damage hoses and
seals.
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Brakes
Brake Master Cylinder
4 Your brake master
cylinder
is here. It is
filled with
DOT-3
brake fluid.
There are only two reasons why the brake fluid level in your master cylinder
might go down. The first is that the brake fluid goes down to an acceptable
level during normal brake lining wear. When new linings are put in, the
fluid level goes back up. The other reason is that fluid is leaking out
of the
brake system. If it is,
you should have your brake system fixed, since a leak
means that sooner or later your brakes won’t work well, or won’t work at
all.
So, it isn’t a good idea to “top off’ your brake fluid. Adding brake fluid
won’t correct
a leak. If you add fluid when your linings are worn, then
you’ll have too much fluid when you get new brake linings. You should add
(or remove) brake fluid, as necessary, only when work is done on the brake
hydraulic system.
Refer to the Maintenance Schedule to determine when to check your brake
fluid. See “Periodic Maintenance Inspections” in the Index.
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Replacing Brake System Parts
The braking system on a modern vehicle is complex. Its many parts have to
be of top quality and work well together if the vehicle is to have really good
braking. Vehicles we design and test have top-quality
GM brake parts in
them, as your vehicle does when it is new. When you replace parts of your
braking system
- for example, when your brake linings wear down and
you have to have new ones put
in - be sure you get new genuine GM
replacement parts. If you don’t, your brakes may no longer work properly.
For example, if someone puts
in brake linings that are wrong for your
vehicle, the balance between your front and rear brakes can change, for the
worse. The braking performance you’ve come to expect can change
in many
other ways
if someone puts in the wrong replacement brake parts.
Other Maintenance Items
Front Suspension and Steering Linkage
Your maintenance schedule will tell you how often to lubricate the fittings.
See “Recommended Fluids and Lubricants” in the Index for the proper
lubricant to use.
Front Wheel Bearing
Your vehicle has front wheel bearings that must be cleaned and repacked.
Your maintenance schedule will tell you how often this must be done.
Front Shock Absorbers
The front shock absorbers of your vehicle do many things. They help the
vehicle ride smoothly and also control the travel of the suspension system.
When the shock absorbers are serviced, any replacement shock absorbers
must be the same as the original equipment shock absorbers
in both
extended length
and strength.
I NOTICE:
If you use shock absorbers that are not the same as the original
shock absorbers, the shock absorbers or suspension system
could be damaged.
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