1993 GMC SIERRA maintenance 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.
-I .. >. ’ , .
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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Cleaning Your Diesel Engine
you spray or pour water or any other liquid on your engine when it is
arm or hot,
or when it is running, you could cause serious damagl o it.
you ever clean the engine, clean it only when it is cold.
Noise Control System
The following information relates to compliance with Federal noi\
se emission
standards for vehicles with a Gross Vehicle Weight Rating (GVW\
R) of more
than 10,000 pounds
(4 536 kilograms). See your maintenance schedule for
information on maintaining the noise control system to minimize degradation
of
the noise emission control system during the life of your vehicle. The noise
control system warranty is given in your Warranty booklet.
These standards apply only to vehicles sold in the United States.
Tampering With Noise Control System Prohibited
Federal law prohibits the following acts or the causing thereof:
1. The removal or rendering inoperative by any person, other t\
han for purposes of maintenance, repair or replacement, of any device
or
element of design incorporated into any new vehicle for the purpose of
noise control, prior to its sale or delivery to the ultimate purchaser or
while it is in use;
or
2. The use of the vehicle after such device or element of design has been
removed or rendered inoperative by any person.
Among those acts presumed to constitute tampering are the acts listed below.
Insulation:
Removal of noise shields or underhood insulation.
Engine:
Removal or rendering engine speed governor, if so equipped, inoperative
so as to allow engine speed to exceed manufacturer specifications.
Fan and Drive:
Removal of fan clutch, if so equipped, or rendering clutch inoperative.
Removal of fan shroud, if so equipped.
Air Intake:
Removal of air cleaner silencer.
Reversing air cleaner cover.
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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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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 where it should be, push the dipstick back in all the
way; then flip the handle down to lock the dipstick in place.
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.
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@IIE, because fluids \
with that
label are especially made for your automatic transmission. Damag\
e caused by
fluid other than
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.
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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
3. Install the filler plug. Be sure that the filler plug is full\
y seated.
level up
to the bottom
of the filler plug hole.
Hydraulic Clutch
112” to
K2376
The hydraulic clutch in your vehicle is self-adjusting. A slight amount of play
(112 inch to an inch) in the pedal is normal.
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Service & Amearance Care
-
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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