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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 toold 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 falls below 0°F (-1 S”C),
because the fuel economy of kerosene isn’t as good as that of diesel fuel.
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 (OOC 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.
If this happens, a WATER
IN FUEL light will come on. If it does, the excess
water must be drained. Your dealer can show
you how to do this.
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Hesitation or “flat” performance at high speed or during \
hard acceleration
may be an indication of premature fuel filter plugging due to dirty or
contaminated fuel. The fidter element may need to be changed
if this
happens. See your dealer for assistance.
To drain water:
1. Stop and park the vehicle in a safe place. Turn off the engine and apply
2. Remove the fuel tank cap.
the parking brake.
3. Place a
fuel-resistant container under the filter drain hose.
5.
6.
7.
8.
4. With the engine
off, open the
water drain valve
2 to 3 turns.
When standing in
front of the
vehicle, the valve
is located on the
right side of the
thermostat
housing.
Start the engine and allow it to idle until clear fuel is ob\
served.
Stop the engine and close the water drain valve.
Remove the fuel-resistant container and properly dispose of the
contaminated fuel.
To find out how to properly dispose of contaminated
diesel fuel see “What to Do with Used Oil” in the “E\
ngine Oil (Diesel
Engines)” part, later in this section.
Install the fuel tank cap.
If the WATER IN FUEL light comes on again after driving a short distance
or the engine runs rough or stalls-a large amount of water has probably
been pumped into the
fuel tank. The fuel tank should be purged.
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Fuels in Foreign Countries (Gasoline Engines)
If you plan on driving in another country outside the U.S. or Canada,
unleaded fuel may be hard to find.
Do not use leaded gasoline. If you use
even one tankful, your emission controls won’t work well or at all. With
continuous use, spark plugs can get fouled, the exhaust system can corrode,
and your engine
oil can deteriorate quickly. Your vehicle’s oxygen sensor
will be damaged.
All of that means costly repairs that wouldn’t be covered
by your warranty.
To check on fuel availability, ask an auto club, or contact a major oil
company that does business in the country where you’ll be driving.
You can also write
us at the following address for advice. Just tell us where
you’re going and give your Vehicle Identification Number
(VIN).
General Motors Overseas Distribution Corporation,
North American Export Sales (NAES)
1908 Colonel Sam Drive
Oshawa, Ontario
LlH 8P7
Filling Your Tank
The fuel cap is behind
a hinged door on
the
left side of your
vehicle.
A CAUTION:
Gasoline vapor is highly flammable. It burns violently, and that
can cause very bad injuries. Don’t smoke
if you’re near gasoline
or refueling your vehicle. Keep sparks, flames, and smoking
materials away from gasoline.
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A CAUTION:
If your vehicle has air conditioning, the auxiliary engine fan
under the hood can start up and injure you even when the
engine is not running. Keep hands, clothing and tools
away from
any underhood electric fan.
A CAUTION:
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
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
I 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 booklet.
These standards apply only
to vehicles sold in the United States.
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Engine Oil (Gasoline Engines)
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.
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.
To Check Engine Oil
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 down.
I
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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 part 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.
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
Oils of the proper quality for your vehicle can be identified by looking for
the “Starburst” symbol. The “Starburst” symbol indicates that the oil has
been certified by the American Petroleum Institute
(API), and is prefenced
for use in your gasoline engine.
If
you change your own oil, be sure you use oil that has the “Starburst”
symbol on the front
of the oil container. If you have your oil changed for
you, be sure the
oil put into your engine is American Petroleum Institute
certified for gasoline engines.
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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
FOR BEST FUEL ECONOMY AND COLD STARTING, SELECT THE LOWEST
SAE VISCOSITY GRADE 011 FOR THE EXPECTED TEMPERATURE RANGE.
HOT
WEATHER
WEATHER
n
c
.
SAE IOW-30
L
LOOK
FOR THIS
SYMBOL
r31.
ip
L c,
SAE SW-30
PREFERRED
DO NOT USE SAE 2OW-50 OR ANY OTHER
GRADE OIL NOT RECOMMENDED
As shown in the chart, SAE 5W-30 is best for your vehicle. However, you
can use SAE IOW-30 if it’s going to be 0°F (-I 8°C) or above. These
numbers on
an oil container show its viscosity, or thickness. Do not use
other viscosity oils, such as
SAE 2OW-SO.
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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
SAE
VISCOSITY GRADE OIL FOR THE EXPECTED TEMPERATURE RANGE.
HOT
WEATHER
SA€ 5W-30
LOOK
FOR THIS
SYMBOL
SAE 10W-30
PREFERRED
above 0°F (‘1 8°C)
COLD
WEATHER
00 NOT USE SA€ 2OW-50 OR ANY OTHER
GRADE OIL NOT RECOMMENDED
As shown in the chart, SAE 10W-30 is best for your vehicle. However, you
can use SAE SW-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 2OW-50.
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