1995 CHEVROLET SUBURBAN Temp

h
9. Then replace the
pressure cap. Be
sure the arrows
on the pressure
cap line up like
this.
Engine Fan Noise
Your vehicle has a clutched engine cooling fan. When the clutch is engaged,
the fan spins faster to provide more air to cool the engine. In most every day
driving conditions the fan
is spinning slower and the clutch is not fully
engaged. This improves fuel economy and reduces fan noise. Under heavy
vehicle loading, trailer towing and/or high outside temperatures,
the fan
speed increases as the clutch more
fully engages. So you may hear an
increase in fan noise. This is normal and should not be mistaken as the
transmission slipping
or making extra shifts. It is merely the cooling system
functioning properly. The fan will slow down when additional cooling is not
required and the clutch partially disengages.
You may also hear this fan noise when you start the engine. It will go away
as the fan clutch partially disengages.
If a Tire Goes Flat
It’s unusual for a tire to “blow out” while you’re driving, especially if you
maintain your tires properly. If air goes out of a tire, it’s much more likely to
leak out slowly. But if you should ever have a “blowout,” here are a few tips
about what
to expect and what to do:
If a front tire fails, the flat tire will create a drag that pulls the vehicle
toward that side. Take your foot off the accelerator pedal and grip the
steering wheel firmly. Steer
to maintain lane position, then gently brake to a
stop well out of the traffic lane.
A rear blowout, particularly on a curve, acts much like a skid and may
require the same correction you’d
use in a skid. In any rear blowout, remove
your foot from
the accelerator pedal. Get the vehicle under control by
steering the way
you want the vehicle to go. It may be very bumpy and
noisy, but you can still steer. Gently brake to a stop, well
off the road if
possible.
If a tire goes flat, the next part shows how to use your jacking equipment to
change a flat tire safely.
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You should ask your service station operators if their gasolines contain
deposit control additives and oxygenates, and
if they have been
reformulated
to reduce vehicle emissions.
Diesel Fuel Requirements and Fuel System
Some states and provinces have restrictions on the purchase of diesel fuel
for light-duty vehicles and require you
to buy permits or pay special taxes.
Some
of these restrictions apply only to residents, and others apply to both
residents and visitors. These restrictions can change.
To learn the current
restrictions
in any state or province, contact your auto club, the police or
other officials.
Fuel Requirements
NOTICE:
Diesel fuel or fuel additives not recommended in this manual
could damage your fuel system and engine. Your warranty
wouldn’t cover this damage. And:
Diesel fuel that has been mixed with engine oil could damage
your engine and emission controls.
Always check with your
service station operator to make sure his diesel fuel has not \
been mixed with engine oil.
If you ever run out of diesel fuel, it can be difficult to restart
your engine. “Running Out
of Fuel,” later in this section, tells
you how to get it started again.
To avoid all this, try never to
let your tank get empty.
What Fuel to Use
For best results, use Number 2-D diesel fuel year-round (above and below
freezing conditions) as
oil companies blend Number 2-D fuel to address
climate differences. Number 1-D diesel fuel may be used
in very cold
temperatures (when it stays below
0°F or -1 8°C); however, it will produce
a power and fuel economy
loss. The use of Number 1-D diesel fuel in warm
or hot climates may result in stalling, poor starting when the engine
is hot
and may damage the fuel injection system.
Diesel fuel may foam when you fill your tank. This can cause the automatic
pump nozzle
to shut off, even though your tank isn’t full. If this happens,
just wait for the foaming
to stop and then continue to fill your tank.
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Canadian Fuels
Diesel-powered trucks are now equipped with emission control systems that
require the use of diesel fuel with low-sulfur
(.05% by weight) content.
Both low- and higher-sulfur fuels will be available
in Canada. Only
low-sulfur diesel fuels are available
in the United States. It is important that
diesel-powered trucks are refueled with low-sulfur fuel. Use of fuels with
higher-sulfur content will affect the function
of the emission components
and may cause reduced performance, excessive smoke and unpleasant odor.
Cold Weather Operation
Follow the instructions listed previously under the heading “What Fuel to
Use
.”
If you’re driving in very cold temperatures and can’t get a “winterized”
Number
2-D that has been adapted to cold weather or a Number 1-D, you
can use one gallon of kerosene for every two gallons of diesel fuel. Once
you add the kerosene, run your engine for several minutes
so the fuels will
mix. Add kerosene only when
the temperature fills below 0°F (-I 8”C),
because the fuel economy of kerosene isn’t as good as that of diesel fuel.
I NOTICE:
Never use home heating oil or gasoline in your diesel engine.
They can cause engine damage.
In cold weather, your fuel filter may become clogged (waxed). To unclog it,
warm the filter to between 32°F and 50°F (0°C to 10°C). You won’t need
to replace it.
Water in Fuel
Sometimes, water can be pumped into your fuel tank along with your diesel
fuel. This can happen if a service station doesn’t regularly inspect and clean
its fuel tanks, or if it gets contaminated fuel from its suppliers.
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If this happens, a WATER IN FUEL light will come
water must be drained. Your Cfpder can show you
hc
I
WATER
IN
FUEL
If the light comes on at any other time, use this chart.
! on. If it does, the excess
3w to do this.
This light
also should
come
on briefly when
you start your engine,
as a check. If it
doesn’t, have it fixed
so it will be there to
let you know if you
ever do get water
in
your fuel.
NOTICE:
If you drive when this warning light is on, you can damage your \
fuel injection system and your engine. If the light comes on \
right
after you refuel,
it means water was pumped into your fuel tank.
Turn off your engine immediately. Then, have the water drained \
at once.
“WATER IN FUEL” LIGHT CHART Problem
Light comes on intermittently.
Light stays on:
Recommended Action
Drain water from fuel filter.
1. At temperatures above freezing. Drain fuel filter immediately. If no
water can be drained and light stays
on, see your dealer for assistance.
2. At temperatures below freezing. Drain fuel filter immediately. If no
water can be drained-water may
be frozen. Open the air bleed valve
to check for fuel pressure. If
no fuel
pressure is present, replace the fuel
filter.
3. Immediately after refueling -
large amount of water possibly
pumped into fuel tank. Fuel tank
purging required. See
your dealer for assistance.
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You should also use the proper viscosity oil for your vehicle, as shown in
the following chart:
LIGHT DUTY EMISSIONS - GASOLINE ENGINES
RECOMMENDED SAE VISCOSITY GRADE ENGINE OILS
FOR BEST FUEL ECONOMY AND COLD STARTING, SELECT THE LOWEST
SAE VISCOSITY GRADE
011 FOR THE EXPECTEO TEMPERATURE RANGE.
HOT
WEATHER
7
'F
t 100
+ 80
+ 60
+ 40
+ 20
0
7
c
+38
- +27
- +16
- +4
--7
--18
WEATHER
-- ....-
SAE 5W-30
PREFERRED
LOOK
FOR THIS
SYMBOL
-
SAE 1OW-30
As shown in the chart, SAE 5W-30 is best for your vehicle. However, you
can use SAE 1 OW-30 if it's going to be 0°F (- 1 SOC) or above. These
numbers on
an oil container show its viscosity, or thickness. Do not use
other viscosity oils, such as SAE 20W-50.
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HEAVY DUTY EMISSIONS - GASOLINE ENGINES
- RECOMMENDED SAE VISCOSITY GRADE ENGINE OILS
FOR BEST FUEL ECONOMY AND COLD STARTING, SELECT THE LOWEST
SAL
VISCOSITY GRADE OIL FOR THE EXPECTED TEMPERATURE RANGE.
- ~~
HOT
WEATHER
/ v
"F
+lo0 c - +38
t8Q - - +27
+60 - +16
+4Q - - +4
+20 ---7
0 ---18
-
-
SAE 1OW-30
PREFERRED
SAE 5W-30
cola
WEATHER
LOOK
FOR THIS
SYMBOL
DO NOT USE SAE 2OW-50 OR ANY OTHER
GRADE OIL NOT RECOMMENDED
As shown in the chart, SAE IOW-30 is best for your vehicle. nowever, you
can use
SAE 5W-30 if it's going to be colder than 60°F (I 6°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 20W-50.
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NOTICE:
Use only engine oil with the American Petroleum Institute
Certified For Gasoline Engines “Starburst” symbol. Failure \
to
use the proper oil can result in engine damage not covered by
your warranty.
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 5 to 10 miles (8 to 16 km). This is particularly
important when outside temperatures are below freezing.
0 Most trips include extensive idling (such as frequent driving in stop and
go traffic).
Most trips are through dusty areas.
You operate your vehicle in dusty areas or off-road frequently.
0 You frequently tow a trailer or use a carrier on top of your vehicle.
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 and filter every 7,500 miles (1 2 500
km) or 12 months - whichever comes first.
Heavy Duty Emissions:
If none of them is true, change the oil and filter every 6,000 miles (10 000
km) or 12 months - whichever comes first.
Engine Coolant Heater
An engine coolant heater can be a big help if you have to park outside in
very cold weather, 0°F (- 18OC) or colder. If your vehicle has this option,
see “Engine Coolant Heater” in the Index.
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DIESEL ENGINES
I RECOMMENDED SAE VISCOSITY 6RADE ENGINE OILS
SELECT THE SAE ORADE OIL BASED ON
THE EXPECTED TEMPERATURE RANGE
BEFORE NEXT 011 CHANGE
HOT
WEATHER
/OF c
+ 100
+BO - -
+32 --
0 -9
-20 -
+ 38
+ 18
SAE 15W-40
PREFERRED
above 0°F (- 1 8°C)
SA€ 1 OW-30
- SA€ I 30
COLD
WEATHER
DO NOT USE 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 (0OC) before your next oil change. When it's very cold, below
0°F (-1 8OC), you should use SAE 1 OW-30 to improve cold starting.
Also, SAE 30 may be used at temperatures above freezing, 32°F (OOC).
These numbers on the oil container show its viscosity, or thickness. Do
not use other viscosity oils such as SAE IOW-40 or SAE 2OW-50.
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