1993 GMC SIERRA service schedule

CAUTION
It can be dangerous to get out of your vehicle if the shift lever is not
fully in
P (Park) with 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 follow.
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
“Parking On Hills” in the Index.
When You Are Ready to Leave After Parklng 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 store the chocks.
Maintenance When Trailer To wing
Your vehicle will need service more often when you’re pulling a trailer. See
the Maintenance Schedule for more on this. Things that are esp\
ecially
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.
mailer Wiring Harness
See “Trailer Wiring Harness’’ in the Index.
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Service & Appearance Care
1 If you try to do your own service work without knowing enough ab\
out it, I
1 your vehicle could be damaged.
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.
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Fuel (Gasoline Engines)
If your vehicle has a diesel engine, see “Diesel Fuel Requi\
rements and Fuel
System’’ in this Section: For vehicles with gasoline engines, please read this.
Use regular unleaded gasoline rated at 87 octane or’higher.
It should meet
specifications ASTM D4814 in the
U.S. and CGSB 3.592 in Canada. These
fuels should have the proper additives,
so you should not have to add
anything to the fuel.
In the
U.S. 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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What to Do with Used Oil:
I
I PAUTION
Used engine oil contains things that have caused skin cancer i\
n I
laboratory animals. Don’t let used oil stay on your skin fo\
r very long.
clnan your skin and nails with soap and water, or a good hand
c,,aner. Wash or properly throw away clothing or rags containing
used engine oil.
I
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 disp\
osal. 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
I I
PO216
Refer to the Maintenance Schedule to determine when to replace \
the air
cleaner filter on diesel engines and the air cleaner filter an\
d crankcase ventilation filter on gasoline engines. See “Scheduled Mainten\
ance Services’’
in the Index.
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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 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.
I Too much or too little fluid can damage your transmission. Too much can
nean that some of the fluid could come out and fall on hot engine parts,
itarting
a fire. Be sure to get an accurate reading if you check your
ransmission ftuid.
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.
To get the right reading, the fluid must be at normal operating temperature,
which is 180°F
to 200°F (82°C to 93°C).
To check the 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 (lO°C), 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 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 (lO"C), you
may have
to idle the engine longer. A hot check must follow when fluid is
added during a cold check.
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Service & Amearance Care
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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 what to add. See
“Owner Checks and Services” and “Recommended Fluids and \
Lubricants” in
the Index.
How to Check:
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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Senrice d& Appearance Cam
Front Axle
When to Check and Change Lubricant:
Refer to the Maintenance Sched,ule to determine
lubricant and when to change it. See “Scheduled
the Index.
How to Check Lubricant:
how often to check the Maintenance Services” in
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.
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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 Bearings
Your vehicle has front wheel bearings that must be cleaned and repa\
cked.
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 absorber\
s
must be the same as the original equipment shock absorbers in both
extended length and strength.
1 NOTICE
If you use shock absomers that are nor me same as the original shock
I absorbers, the shock absorbers or suspension system could be da\
maged.
Wheel Nut Torque
For vehicles with dual wheels, when the vehicle, wheel or fast\
eners are new,
have the torque set at the first
100, 1,000 and 6,000 miles (160, 1600 and
9600 km). Use the torque specified in the appropriate Specification \
Chart later
in this section.
Single Belt Accessory Drive
If your new vehicle uses a serpentine belt, it is lighter, and more durable
than systems with several belts.
The belt runs over or around the pulleys
on the engine. A tensioner is used
to keep the belt tight at all times. The tensioner also makes replacing the
belt easier.
If you need to replace the belt, be sure to get the correct
replacement belt. Your dealership
or parts supplier can help you with this.
The Accessory Drive Belt Routing label on your vehicle will sh\
ow you how to
route the belt your vehicle uses.
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Service & Appearance Care
Windshield Wiper Blade Inserts
I -
r
PO232
To replace the windshield wiper blade insert, lift the wiper arm and rotate the
blade until it is facing away from the windshield. Unlatch the\
end of the insert
from the holding clips. Remove the insert and slide a new one\
in place.
Make sure the blade is secured in the clips.
Air Conditioning
Every now and then have your dealership check your air conditi\
oning system
to be sure it has not lost any cooling ability.
If you think the system is not
working properly, have your dealership check it out as soon as\
possible.
The air conditioning will not work when the temperature is bel\
ow 40°F
(4°C).
Fluid Leak Check
After the vehicle has been parked for a while, inspect the su\
rface under the
vehicle
for water, oil, fuel or other fluids. Water dripping from the air
conditioning system after it has been used is normal, If you notice fuel leaks
or fumes, the causes should be found and corrected at once.
Lubrication
Accelerator Control System
Your maintenance schedule will tell you how often the accelerator linkage
pivot points must be lubricated. See “Recommended Fluids and \
Lubricants” in
the Index for the proper lubricant to use.
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