engine GMC SIERRA 1994 Owners Manual

To Check Engine Oil
Pull out the dipstick and clean it with a paper towel or a cloth, then push it
back in all the way. Remove it again, keeping the tip lower.
When to Add Oil
If the oil is at or below the ADD line, then you’ll need to add some oil. But
you must use the right kind. This section explains what kind
of oil to use.
For crankcase capacity, see “Capacities and Specifications” in
the Index.
NOTICE:
Don’t add too much oil. If your engine has so much oil that the
oil level gets above the proper operating range, your engine
could be damaged.
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The engine oil filler
cap
is located on a
filler tube at the front
of the engine.
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.
What Kind of Oil to Use
Look for these two things:
CF4SH
CF4SH is the best oil for your vehicle. However, if you can not find
CF4/SH oil, you may use CF-4/SG or CE/SH or CE/SG oil.
These may be listed
as shown or in reverse order, for example SHEF-4.
Other letters may also be listed, such as SH/CD, CE, CF-4. These letters
show American Petroleum Institute (API) levels of quality.
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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DIESEL ENGINES
RECOMMENDHI SAE VISCOSITY GRADE ENGINE OILS
SELECT THE SAE GRADE OIL BASED ON
THE EXPECTED TEMPERATURE RANGE
BEFORE NEXT
OIL CHANGE
HOT
WEATHER
;F
k 100
+60 --+16
+32 -- 0
0 -- -18
-20 - -29
---I
---I SAE low*
SAE 15W-40
PREFERRED
above 0°F (- 18%)
830
I SAE r 30
COLD
WEATHER
DO NOT USE SAE 1OW-40, SAE 2OW-50 OR
ANY OTHER GRADE OIL NOT RECOMMENDED
SAE 15W-40
As shown in the viscosity chart, SAE 15W-40 is best for your vehicle.
However, you can use
SAE 1OW-30 if it’s going to be colder than
32°F (0°C) before your next oil change. When it’s very cold, below
0°F (-I 8OC), you should use SAE 1,0W-30 to improve cold starting.
Also, SAE 30 may be used at temperatures above freezing, 32°F (0°C).
These numbers on the oil container show its viscosity, or thickness. Do
not use other viscosity oils such as SAE 10W-40 or SAE 2OW-50.
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This doughnut-shaped logo (symbol) is used on most oil containers 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:
0 Most trips are less than 4 miles (6 km).
0 It’s below freezing outside and most trips are less than 10 miles
(16 km).
0 The engine is at low speed most of the time (as in door-to-door
delivery, or in stop-and-go traffic).
0 You tow a trailer often.
0 Most trips are through dusty places.
The vehicle is frequently operated off-road.
If any
of these is true for your vehicle, then you need to change your oil and
filter
every 2,500 miles (4 000 km) or 3 months - whichever comes first.
If
none of them is true, change the oil and filter every 5,000 miles
(8 000 km) or 12 months - whichever comes first.
What to Do with Used Oil
Did you know that used engine oil contains certain elements that may be
unhealthy for
your skin and could even cause cancer‘? 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. (See the manufacturer’s warnings about the use
and disposal
of oil products.)
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.
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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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.-. -1 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.
Then, unhook the
cover retaining clips
and push the rear
of
the cover toward the
engine.
Automatic Transmission Nuid
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 SLIK to follow all the instructions here, or you could
get a false reading on the dipstick.
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I 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.
Wait at least 30 minutes before checking the transmission fluid level if you
have been driving:
0 When outside temperatures are above 90°F (32°C).
At high speed for quite a while.
0 In heavy traffic - especially in hot weather.
While pulling a trailer.
IU get the right reading, the fluid should be at normal operating
temperature, which
is 180°F to 200°F (82°C to 93°C).
To check trunsmissioltfluid 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 trmzsnzissiorz jZuid 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. Should the fluid level be low during a cold check,
you must perform a hot check before adding fluid. This will give you a
more accurate reading of the fluid level.
To check the fluid hot or cold
Park your vehicle on a level place.
With the parking brake applied, place the shift lever in “P” (Park).
With your foot on the brake pedal, move the shift lever through each
gear range, pausing for about three seconds
in each range. Then,
position
the shift lever in “P’ (Park).
Let the engine run at idle for three minutes or more.
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Then, .without shutting ofithe engine, follow these steps:
1. Flip the handle
up and then pull
out the dipstick
and wipe it with a
clean rag
or paper
towel.
2. Push it back in all
the way, wait
three seconds and
then pull it back
out again.
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 in the
acceptable range,
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
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 tluid, generally less than a pint. Don’t overfill. We
recommend you use only fluid labeled DEXRON@-111 or DEXRON@-IIE,
because fluids with that label are made especially for your automatic
transmission. Damage caused by fluid other than
DEXRON@-Ill 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 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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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 OF (-29”C), or -34°F (-37°C) in
Canada and for vehicles with the cold climate option.
Give boiling protection up to 258 OF ( 125 O C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning lights and gages work as they should.
What to Use
Use a mixture of one-half clean wuter (preferably distilled) and one-half
antifreeze that meets
“GM Specification 6038-M,” which won’t damage
aluminum parts.
You can also use a recycled coolant conforming to “GM
Specification 6038-M” with a complete coolant flush and refill. If you use
this mixture, you don’t need to add anything else.
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