service GMC SIERRA 1995 Owner's Guide

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 conditionsj 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 -18°C); however, it will produce
a power and fuel economy loss. The use of Number I-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.
A CAUTION:
Heat coming from the engine may cause the fuel to expand and \
force the fuel out of your tank.
If something ignites the fuel, a
fire could start and people could be burned. To help avoid this,
fill your fuel tank only until the automatic nozzle shuts
off.
Don’t try to “top it off.”
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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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Engine Coolant Heater
An engine coolant heater can be a big help if you have to park outside in
very cold weather, 0°F (-1 8OC) or colder. If your vehicle has this option,
see “Engine Coolant Heater’’ in the Index.
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.
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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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 5 to IO 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
e 00 traffic).
0 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 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
To avoid the possibility of un-filtered air being drawn into the engine, make
sure the air cleaner cover
is on straight and the wing nuts are properly
tightened. If there
is an arrow on the air cleaner cover, it should point to the
front of the engine.
Refer to the Maintenance Schedule to determine when to replace
the air
filter.
See “Scheduled Maintenance Services”
in the Index.
A CAUTION:
Operating the engine with the air cleaner off can cause you or
others to be burned. The air cleaner not only cleans the air, it
stops flame if the engjne backfires.
If it isn’t there, and the
engine backfires, you could be burned. Don’t drive with it
off,
and be careful working on the engine with the air cleaner off.
I NOTICE: I
If the air cleaner is off, a backfire can cause a damaging engine
fire. And, dirt can easily get into your engine, which will damage
it. Always have the air cleaner in place when you’re driving.
To remove the air cleaner filter on a gasoline engine or a 6.5 liter naturally
aspirated diesel engine, turn the wing nuts to the left. Remove the cover and
change
the filter.
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To remove the air cleaner filter on a 6.5 liter turbocharged diesel engine,
first remove the rubber elbow. Remember to observe the caution about
turbocharger blades on the rubber elbow.
Then, unhook the
cover retaining clips
and push the rear
of
the cover toward the
engine.
Automatic Transmission Fluid
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 your
GM dealer Service Department.
If you do
it yourself, be sure to follow all the instructions here, or you could
get
a false reading on the dipstick.
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 parts, starting a fire. Be \
sure
to get an accurate reading if you check your transmission fluid.
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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.
Add fluid only after checking the transmission fluid
HOT. (A COLD check
is used
only as a reference.) If the fluid level is low, add only enough of the
proper fluid to bring the level up
to the HOT area for a hot check. It doesn’t
take much fluid, generally less than a
int. Don ’t overfill. We recommend
you use only fluid labeled DEXRON
-111, because fluid with that label is
made especially for your automatic transmission. Damage caused by fluid
other than DEXRON@-I11 is not covered by your
new vehicle warranty.
8
0 After adding fluid, recheck the fluid level as described under “How to
Check.”
0 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 Transmission 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 your
GM dealer 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 parts, 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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When to Check and What to Use
Refer to the
Maintenance Schedule
to determine how
often
you should
check the
fluid level
in your clutch master
cylinder reservoir and
d for the proper fluid.
See “Owner Checks and Services” and “Recommended Fluids and
Lubricants”
in the Index.
How to Check
The proper fluid should be added if the level does not reach the bottom of
the diaphragm when it’s in place in the reservoir. See the instructions on the
reservoir cap.
Rear Axle
When to Check and Change Lubricant
Refer to the Maintenance Schedule to determine how often to check the
lubricant and when to change
it. See ”Scheduled Maintenance Services’‘ in
the Index.
How to Check Lubricant
If the level is below
the bottom of the filler
plug hole, you’ll need
to add some lubricant.
Add enough lubricant
to raise the level to the
bottom of the filler
plug hole.
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How to Check Lubricant
What to Use
If the level is below
the bottom
of the filler
plug hole, you’ll need
to add some lubricant.
Add enough lubricant
to raise the level
to the
bottom of the
filler
plug hole.
Refer to the Maintenance Schedule to determine what kind of lubricant to
use. See “Recommended Fluids and Lubricants” in the Index.
Front Axle
When to Check and Change Lubricant
Refer to the Maintenance Schedule to determine how often to check the
lubricant and when to change it. See “Scheduled Maintenance Services”
in
the Index.
How to Check Lubricant
If the level is below the bottom of the filler plug hole, you’ll need to add
some lubricant.
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Brake Wear
Your vehicle has front disc brakes and rear drum brakes. If you have a C
3500 HD model, it has four-wheel disc brakes.
Disc brake pads have built-in wear indicators that make
a high-pitched
warning sound when the brake pads are worn and new pads are needed. The
sound may come and
go or be heard all the time your vehicle is moving
(except when you are pushing on the brake pedal firmly).
I A CAUTION:
The brake wear warning sound means that sooner or later your
brakes won’t work well. That could lead to an accident. Whe\
n
you hear the brake wear warning sound, have your vehicle
serviced.
NOTICE:
Continuing to drive with worn-out brake pads could result in
costly brake repair.
Some driving conditions or climates may cause a brake squeal when the
brakes are first applied or lightly applied. This does not mean something is
wrong with your brakes.
If you have rear drum brakes, they don’t have wear indicators, but if you
ever hear
a rear brake rubbing noise, have the rear brake linings inspected.
Also, the rear brake drum should be removed and inspected each time the
tires are removed for rotation
or changing. When you have the front brakes
replaced, have the rear brakes inspected, too.
Brake linings should always be replaced as complete axle sets.
Brake Pedal Travel
See your dealer if the brake pedal does not return to normal height, or if
there is a rapid increase in pedal travel. This could be a sign of brake
trouble.
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