1994 GMC SIERRA Owners Manual

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 km).
The engine is at low speed most of the time (as in door-to-door
delivery, or
in stop-and-go traffic).
You tow a trailer often.
Most trips are through dusty places.
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 3,000 miles (5 000 km) or 3 months - whichever comes
first.
Light Duty Emissions:
If none of them is true, change the oil every 7,500 miles (12 500 km) or
12 months
- whichever comes first. Change the filter at the first oil change
and at every other oil change after that.
Heavy Duty Emissions:
If none of them is true, change the oil every 6,000 miles (10 000 km) or
12 months - whichever comes first. Change the filter at the first oil change
and at every other oil change after that if mileage determines when you
change
your oil. If time determines when you change your oil, change the
filter each time you change your oil.
Engine Coolant Heater (Engine Block Heater)
An engine coolant 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 Coolant Heater
” in the Index.
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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 t.o drain all free-tlowing
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.
Engine Oil (Diesel Engines)
It's a good idea to check your engine oil level every time you get fuel. In
order
to get an accurate reading, the oil must be warm and the vehicle must
be
on level ground.
Turn off
the engine
and give the oil
a few
minutes to drain back
into
the oil pan. If you
don't, the
oil dipstick
might
not show-the
actual
level.
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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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