service GMC SIERRA 1993 Service Manual

r
Service & Appearance Care
Just fill it enough to put the level somewhere in the proper operating range.
Push the dipstick all the way back in when you’re through.
I’ I
What Kind of Oil to Use:
Look for these two things:
CElSG
K2396
I’ : .I
For SAE 15W-40 or SAE 1OW-30, CE must be on the oil container. For
SAE
30, CD must be there. These may be listed alone or with letters,
such as
CEISG, CE/SG/SF, SGICD, etc. These letters show the
American Petroleum Institute (API) levels
of qualijr.
NOTICE
If you use oils that don’t have these designations, you can cause engine
damage which
is not covered by your warranty.
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Service & Appearance Cam
heavy-duty applications at temperatures above freezing, 32°F (O’C), SAE
30 grade oil is recommended.
These numbers on an oil container show its viscosity, or thickness.
Do not use other viscosity oils such as
SAE IOW-40 or SAE 2OW-50.
This doughnut-shaped logo (symbol) is used on most oil contai\
ners to help
you select the correct oil.
You should
look for this on the oil container, and use only those oils that
display the logo.
GM Goodwrench@ oil (in Canada, GM Engine Oil) meets all the \
requirements
for your vehicle.
Engine Oil Additives:
Don’t add anything to your oil. Your GM dealer is ready to advise if you think
something should be added.
When to Change Engine Oil:
See if any one of these is true for you:
Most trips are less than 4 miles (6 km).
It’s below freezing outside and most trips are less than 10 miles (16
The engine is at low speed most of the time (as in door to door
You tow a trailer often.
Most trips are through dusty places. km).
delivery, or in stop-and-go traffic).
The vehicle is frequently operated off-road .
If any one of these is true for your vehicle, then you need to change your
oil and filter every 2,500 miles (4000 km) or 3 months-whichever comes
first.
If none of these is true, change the oil and filter every 5,000 miles (8000
km) or 12 months-whichever comes first.
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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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Service & Appearance Care
I
IC 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, you
could be burned. Don't drive with it
off, and be careful working on
the engine with the air cleaner
off.
If the air cleaner is off, a backfire can cause a damaging engine fire. And,
dirt can easily get into your engine, which will dan le
it. Alway! 3 tl
air cleaner in place when you're driving.
To remove the air cleaner filter on a gas engine, turn the wing nuts
counterclockwise. Remove the cover and change the filter.
fi 31 Fnning 6.5L Engine
K2151
On a 6.2L diesel engine there are two wing nuts. On a 6.5L \
diesel engine, unhook the clips.
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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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*
Senrice & Appearance Care
Manual Transmission Huld
When to Check:
the fluid in your manual transmission doesn't require changing.
How to 'Check:
Because this operation can be a :little difficult, you may cho\
ose to have this
done at your dealership Service Department.
t A good time to have it checked is when .the engine oil is changed. However,
If you do it yourself, be sure to follow' all the instructions here, or you could
get a false reading..
. . .. . . ... -
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,
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 re\
st your fingers
on the transmission case.
Then, follow these steps:.
~ ~~ ~
1. Remove the filler plug.
K2471
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.
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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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Service & Appearance ,Care
Engine Coolant
r
PO593
The following explains your cooling system and how to add cool\
ant 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 -34°F (-37°C).
Give boiling protection up to 258°F (125°C).
Protect against rust and corrosion:
Help keep the proper engine temperature.
Let the warning lights and gages work as thiy should.
What to Use:
Use a ,mixture of clean water (preferably distilled), and antifreeze that meets
“GM Specification 6038-M,” which won’t damage aluminum p\
arts.
Also use
GM Engine Coolant Supplement (sealer) with a complete coolant change. If
you use these, you don’t need to add anything else.
,
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1 CAUTION
4 Adding only plain water to your cooling system can be dangerous.
Plain water, or some other liquid like alcohol, can boil before th(
)per coolant mix will. Your vehicle’s coolant warning system is set
for the proper coolant mix. With plain water or the wrong mix\
, your
engine could get too hot but you wouldn’t get the overheat warning.
Your engine could catch fire and you or others could be burned. Use
a
50/50 mix of clean water and a proper antifreeze.
NOTICE
If you use an improper coolant mix, your engine could overheat an\
d 1:
badly damaged. The repair cost wouldn’t be covered by your warranty. 1
much water in the mix can freeze and xk +?e t line radiator, heater
core and other parts.
Some conditions, such as air trapped in the cooling system, can affect the
coolant level in the radiator. Check the coolant level when the engine is cold
and follow the steps under “Adding Coolant” for the prope\
r way to add
coolant.
If you have the low coolant warning system, refer to the General Motors
Service Manual or see your dealer for the proper coolant
fill procedure. (To
purchase a Service Manual, see “Service Publications’’ in the Index.) Using
the wrong
fill procedure can cause a low coolant warning indication.
If you have to add coolant more than four times a year, have your dealer
check your cooling system.
If you use the proper coolant, you don’t have to add extra inhibitors or
additives which claim to improve
the system. These can be harmful.
-
NOTICE .I
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