1994 GMC SIERRA Owners Manual

Checking Things Under the Hood
Iood Release
To open the hood, first
pull the handle inside
the vehicle.
Then go to the front
of
the vehicle and pull up
on the secondary hood
release, located just to
the passenger side of
the center of the grill.
Lift the hood.
Your vehicle,
if it has
air conditioning, may
have a auxiliary engine fan in addition
to the belt driven fan.
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Things that burn can get on hot engine parts and start a fire.
These include liquids like gasoline or diesel fuel, oil, coolant,
brake fluid, windshield washer and other fluids, and plastic or
rubber. You or others could be burned. Be careful not to drop or
I spill things that will burn onto a hot engine.
Before closing the hood, be sure all filler caps are on properly. Pull down
the hood and close it firmly.
Cleaning Your Diesel Engine
NOTICE:
If you spray or pour water or any other liquid on your engine
when it is warm or hot, or when it is running,
you could cause
serious damage to it.
If you ever clean the engine, clean it only
when it is cold.
Noise Control System
The following information relates to compliance with Federal noise
emission standards for vehicles
with a Gross Vehicle Weight Rating
(GVWR) of more than
10,000 pounds (4 536 kilograms). The Maintenance
Schedule booklet provides 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 hooklet.
These standards apply only to vehicles sold
in the United States.
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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 than 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.
Exhaust:
Removal of muffler and/or resonator.
Removal of exhaust pipes and exhaust pipe clamps.
Engine Oil (Except Diesel)
It’s a good idea to check your engine oil 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.
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I
I
I
To Check Engine Oil
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.
Pull out the dipstick and clean it with
a paper towel or 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 mark, 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 upper mark that shows the proper
operating range, your engine could be damaged.
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The engine oil filler
cap is located on
the
driver’s side engine
valve cover.
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
Beginning midyear 1993, oils of the proper quality for your vehicle will be
identified with this new “starburst” symbol. The “starburst” symbol
indicates that
the oil has been certified by the American Petroleum Institute
(API), and
is preferred for use in your gasoline engine.
YOU should look for this on the front of the oil container, and use only oils
that display this new symbol.
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You should also use the proper viscosity oil for your vehicle, as shown in
the following chart:
LIGHT DUTY EMISSIONS -GAS ENGINES
RECOMMENDED SAE VISCOSITY GRADE ENGINE OILS
FOR BEST FUEL ECONOMY AND COLD STARTING, SELECT THE LOWEST
SAE VISCOSITY GRADE OIL
FOR THE EXPECTED TEMPERATURE RANGE.
HOT
WEATHER
F
tlOO -
+80 -
+60 -
+40 -
+20 -
0-
C
t 38
t 27
t 16
t4
-7
- 18
m LOOK
ONE OF THESE
LABELS
-- -1 -I SAE 1OW-30
IF NEITHER SAE 5W-30 NOR SAE 1OW-30
5w-30 GRADE OILS ARE AVAILABLE, SAE 30
PREFERRED GRADE MAY BE USED AT TEMPERATURES
ABOVE
40 DEGREES F (4 DEGREES C).
DO NOT USE SAE 1OW-40, SAE 2OW-50 OR
ANY OTHER GRADE OIL NOT RECOMMENDED
As shown in the chart, SAE SW-30 is best for your vehicle. However, you
can use SAE 1OW-30 if it’s going to be 0°F (-1 8°C) or above. These
numbers on an
oil container show its viscosity, or thickness. Do not use
other viscosity oils, such as SAE lOW-40 or SAE 20W-50.
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HEAVY DUTY EMISSIONS -GAS ENGINES
RECOMMENDED SAE VISCOSITY GRADE ENGINE OILS
FOR BEST FUEL ECONOMY AND COLD STARTING, SELECT THE LOWEST
SAE VISCOSITY GRADE OIL
FOR THE EXPECTED TEMPERATURE RANGE.
HOT
WEATHER
m
“F OC
+loo - - +3a
+80 - - +27
+60 --+16
+40--+4
+20---7
0 ---18
I SAE
COLD
WEATHER
LOOK FOR
ONE OF THESE
LABELS
SAE 1OW-30
PREFERRED
above 0°F (-1 SOC)
~ 5W-30
IF NEITHER SAE 5W-30 NOR SAE 1OW-30
GRADE OILS ARE AVAILABLE, SAE 30
GRADE MAY BE USED AT TEMPERATURES
ABOVE
40 DEGREES F (4 DEGREES C).
ANY OTHER GRADE
OIL NOT RECOMMENDED
DO NOT USE SAE 1OW-40, SAE 2OW-50 OR
As shown in the chart, SAE 1OW-30 is best for your vehicle. However, you
can use
SAE 5W-30 if it’s going to be colder than 60°F (16°C) before your
next
oil change. When it’s very cold, you should use SAE 5W-30. These
numbers on an oil container
show its viscosity, or thickness. Do not use
other viscosity oils, such as
SAE low40 or SAE 20W-50.
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If you cannot find oils with the new “starburst” symbol on the front of the
container,
you should look for and use oils containing the following three
things:
SHor SG
“SH” or “SG” must be on the oil container, either by itself or combined
with other quality designations, such as “SH/CD,” “SH,SG,CD,”
“SG/CD,” etc. These letters show American Petroleum Institute (API)
levels of quality.
0 SAE 5W-30 -Vehicles with Light Duty Emissions (SSOO GVWR or
less) OR
SAE 1 OW-30 -Vehicles with Heavy Duty Emissions (850 1 GVWR or
more).
0 Energy Conserving I1
Oils with these words on the container will help you save fuel.
These three things are usually included
in a doughnut shaped logo (symbol)
on most containers. If you cannot find oils with the “starburst” symbol, you
should look for oils with the doughnut shaped symbol, containing the three
things noted above.
NOTICE:
If you use oils that do not have either the “starburst” symbol or
an
API SH or SG designation, you can cause engine damage not
covered by your warranty.
GM Goodwrench@ oil (in Canada, GM Engine Oil) meets all the
requirements for your vehicle.
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