1993 CHEVROLET SUBURBAN service schedule

. .
6. Release the regular brakes.
CAUTION
It can be dangerous to get out of your vehicle if the shift lever is no
fully in
P (Park) wi-. the parking brake firmly set. Your vehicle can
roll.
If you have left the engine running, the vehicle can move suddenl\
y.
You or others could be injured.
To be sure your vehicle won’t move,
when you’re on fairly level ground, use the steps that foll\
ow.
If you have four-wheel drive and your transfer case is in N (Neutral),
your vehicle will be free to
roll, even if your shift lever is in P (Park)
So, be sure the transfer case is in a drive gear-not in N (Neutral).
If you are parking on a hill, or if you’re pulling a trailer, also see
I “Parking On Hills” in the Index. I
When You Are Ready to Leave After Parking on a Hill
1. Apply your regular brakes and hold the pedal down while you:
Start your engine.
Shift into a gear; and
Release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and stow the chocks.
Maintenance When Trailer Towing
Your vehicle will need service more often when you’re pulling a \
trailer. .See
the Maintenance Schedule for more on this. Things that are especially
important in trailer operation are automatic transmission fluid (don’t overfill),
engine oil, axle lubricant, belts, cooling system, and brake ad\
justment. Each
of these is covered in this manual, and the Index will help you find them
quickly.
If you’re trailering, it’s a good idea to review these sections before
you start your trip.
Check periodically to see that all hitch nuts and bolts are tight.
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If you try to do your own service work without knowing enough about it,
your vehicle could be damaged.
I
Maintenance Schedule
Section 7 of this manual, “Scheduled Maintenance Services”, explains \
the
maintenance your new vehicle needs, and when
it should be done. It also
has a
form that you can use to record the maintenance work done on your
vehicle. Be sure to read this information.
Fuel
I K228
Use regular unleaded gasoline rated at 87 octane or higher. It should meet
specifications
ASTM D4814 in the U.S. and CGSB 3.5-92 in Canada. These
fuels should have the proper additives,
so you should not have to add
anything
to the fuel.
In the
US. and Canada, it’s easy to be sure you get the right kind of
gasoline (unleaded). You’ll see UNLEADED right on the pump. And only
unleaded nozzles will
fit into your vehicle’s filler neck.
Be sure the posted octane is at least
87. If the octane is less than 87, you
may get a heavy knocking noise when you drive. If it’s bad enough, it can
damage your engine.
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Service & Appearance Care
oil. If time determines when you change your oil, change the filter ea\
ch time
you change your oil.
Engine Block Heater:
An engine block heater can be a big help if you have to park outside in very
cold weather,
0°F (-18°C) or colder. If your vehicle has this option, see
“Engine Block Heater” in the Index.
What to Do with Used Oil:
Used engine oil contains things that have caused skin cancer in
laboratory animals. 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.
. ,A:<< --.
L. .. . .. ,-. f .- , L ., -J ’,: ._ - -
..:.: ;,i, j I -.. : j ,!
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.
Air Cleaner
c
PO21 6
Refer to the Maintenance Schedule to determine when to replace the air
cleaner filter and crankcase ventilation filter. See “Schedule\
d Maintenance Services” in the Index.
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I CAUTION
I 10 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, y(--
could be burned. Don’t drive with it
off, and be cr-ful working on
the engine with the air cleaner
off.
~
NOTICE I
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.
Ib remove the air cleaner filter on a gas engine, turn the wing nuts
counterclockwise. Remove the cover and change the filter.
-
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 General Motors dealership Sewice 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 I
I
Too much or too little fluid can damage your transmission. Too much can
mean that some of the fluid could come out and fail
on hot engine parts,
I
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:
When outside temperatures are above 90°F (32°C).
At high speed for quite a while.
In heavy traffic-especially in hot weather.
While pulling a trailer.
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Service & Appearance Cave
When to Check and What to Use:
K2343
Refer to the Maintenance Schedule to determine how often you should check
the fluid level in
your clutch master cylinder reservoir and what to add. See
"Owner Checks and Services" and "Recommended Fluids and Lubrican\
ts" in
the Index.
Now to Check:
I
K2344
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.
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Service & Appearance Care
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:
PO231
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.\

Rear 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 “Recommended Fluids and Lubricants”
in the Index.
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Service & Appearance Care
i .. c
K2694
What to Add:
Refer to the Maintenance Schedule to determine what kind of fluid to use.
See “Recommended Fluids and Lubricants” in the Index.
NOTICE I
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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Service & Appearance Care
Brake Master Cylinder
Your brake master cylinder is here. It is filled with DOT-3 brake fluid.
P
K2470
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.
.
4 If you---have too much brake fluid, it can spill on the engine. The fluid
will burnhhe engine is hot enough. You or others could be burned,
and your vehicle could be damaged. Add brake fluid 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” in the Index,
To Check Brake Fluid:
You can check the brake fluid without taking off the cap. Just look at the
windows on the brake fluid reservoir. The fluid levels should \
be above the
MIN
mark. If they aren’t, have your brake system checked to see if there is a leak.
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