engine GMC SIERRA 1998 Owners Manual

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 dealership
Service Department.
If you do it yourself, be sure to follow all the
instructions here, or you could get a fdse 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.
Then, follow these steps:
I. Remove the filler plug.
2. Check that the lubricant level is up to the bottom of
the filler plug hole.
3. If the fluid level is good, install the plug and be sure
it is fully seated. If the fluid level is low, add more
fluid as described in the next steps.
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How to Check Lubricant
If the level is below the bottom of the filler plug hole,
you may need to add some lubricant.
When the differential is cold, add enough lubricant to
raise the level to 1/2 inch (12
mrn) below the filler
plug hole.
When the differential is at operating temperature
(warm), add enough lubricant to raise the level to the
bottom
of the filler plug hole.
What to Use
Refer to the Maintenance Schedule to determine what
kind of lubricant to use. See “Recommended Fluids and
Lubricants” in the Index.
Engine Coolant
The cooling s stem in your vehicle is filled with
DEX-COOL engine coolant. This coolant is designed
~
to remain in your vehicle for 5 years or 150,000 miles I
(240 000 km) whichever occurs first, if you add only ~
DEX-COOL’ extended life coolant.
8
The following explains your cooling system and how
to add coolant when it is low. If you have a problem
i
with engine overheating, see “Engine Overheating” in 1
the Index.
A 50/50 mixture of water and DEX-COOL@ coolant will: 1
0 Give freezing protection down to -34°F (-37°C).
0 Give boiling protection up to 265 OF (1 29 O C).
Protect against rust and corrosion.
0 Help keep the proper engine temperature.
0 Let the warning gages work as they should.
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NOTICE:
When adding coolant, it is important that you use
only
DEX-COOL@ (silicate-free) coolant.
If coolant other than DEX-COOL is added to the
system, premature engine, heater core or
radiator corrosion may result. In addition, the
engine coolant will require change sooner
-- at
30,000 miles (50 000 km) or 24 months,
whichever occurs first. Damage caused by the use
of coolant other than DEX-COOL@ is not
covered by your new vehicle warranty.
What to Use
Use a mixture of one-half clean water (preferably
distilled) and one-half
DEX-COOL@ coolant which
won’t damage aluminum
parts. If you use this mixture,
you don’t need to add anything else.
CAUTION:
Adding only plain water to your cooling system
can be dangerous. Plain water, or some other
liquid like alcohol, can boil before the proper
coolant mixture will. Your vehicle’s coolant
warning system is set for the proper coolant
mixture. With plain water or the wrong mixture,
your engine could get too hot but you wouldn’t
get the overheat warning. Your engine could
catch fire and you or others could be burned.
Use a
50/50 mixture of clean water and
DEX-COOL@ coolant.
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- ~ ~~
NOTICE:
If you use an improper coolant mixture, your
engine could overheat and be badly damaged.
The repair cost wouldn’t be covered by your
warranty.
Too much water in the mixture can
freeze and crack the engine, radiator, heater core
and other parts.
If you have to add coolant more than four times a year,
have your dealer check your cooling system.
NOTICE:
If you use the proper coolant, you don’t have to
add extra inhibitors or additives which claim
to
improve the system. These can be harmful.
Checking Coolant
If your vehicle has a diesel engine, see “Checking
Coolant”
in the Diesel Engine Supplement.
,:. . .,. ..... I.. .;> .:... ...,,.. ::l:. ..
.. .
The coolant recovery tank is located on the passenger’s
side at the rear corner
of the engine compartment.
When your engine
is cold, the coolant level should be at
the
COLD mark, or a little higher. When your engine is
warm,
the level should be up to the HOT mark, or a
little higher.
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Adding Coolant
If you need more coolant, add the proper DEX-COOL@
coolant mixture at the coolant recovery tank.
,
A CAUTION:
'krning the radiator pressure cap when the
engine and radiator are hot can allow steam
and scalding liquids to blow out and burn you
badly. With the coolant recovery tank, you will
almost never have to add coolant at the radiator.
Never turn the radiator pressure cap
-- even a
little
-- when the engine and radiator are hot.
Add coolant mixture at the recovery tank, but be careful
not to
spill it.
A CAUTION:
You can be burned if you spill coolant on hot
engine parts. Coolant contains ethylene glycol,
and it
will burn if the engine parts are hot
enough. Don't spill coolant on a hot engine.
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Radiator Pressure Cap
(Gasoline Engine)
The radiator pressure cap must be tightly installed with
the arrows
on the cap lined up with the overflow tube on
the radiator filler neck.
~~~ ~
NOTICE:
Your radiator cap is a 15 psi (105 kPa)
pressure-type cap and must be tightly installed to
prevent coolant loss and possible engine damage
from overheating. Be sure the arrows on the cap
line up with the overflow tube on the radiator
filler neck.
Thermostat
Engine coolant temperature is controlled by a thermostat
in the engine coolant system. The thermostat stops the
flow of coolant through the radiator until the coolant
reaches a preset temperature.
When you replace your thermostat, an
AC@ thermostat
is recommended.
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Power Steering Fluid
When to Check Power Steering Fluid
It is not necessary to regularly check power steering fluid
unless you suspect there is
a leak in the system or you hear
an unusual noise.
A fluid loss in this system could indicate
a problem. Have the system inspected and repaired.
How To Check Power Steering Fluid
When the engine compartment is cool, wipe the cap and
the top of the reservoir clean, then unscrew the cap and
wipe the dipstick
with a clean rag. Replace the cap and
completely tighten it. Then remove the cap again and
look at the fluid level on the dipstick.
The level should be at the FULL
COLD mark. If
necessary, add only enough fluid
to bring the level up to
the mark.
What to Use
To determine what kind of fluid to use, see
“Recommended Fluids and Lubricants”
in the Index.
Always use the proper fluid. Failure to use the proper
fluid can cause leaks and damage hoses and seals.
Windshield Washer Fluid
What to Use
When YOLI need windshield washer fluid, be sure to read
the manufacturer‘s instructions before use.
If you will be
operating your vehicle
in an area where the temperature
may
fdll below freezing, use a fluid that has sufficient
protection against freezing.
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Adding Washer Fluid
Open the cap labeled WASHER FLUID ONLY. Add
washer fluid until the tank is full.
1
NOTICE:
0
0
0
0
When using concentrated washer fluid,
follow the manufacturer’s instructions for
adding water.
Don’t mix water with ready-to-use washer
fluid. Water can cause the solution to freeze
and damage your washer fluid tank and
other parts of the washer system. Also,
water doesn’t clean as well as washer fluid.
Fill your washer fluid tank only
three-quarters full when it’s very cold. This
allows for expansion if freezing occurs,
which could damage the tank if it is
completely full.
Don’t use engine coolant (antifreeze) in
your windshield washer. It can damage
your washer system and paint.
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Brakes
Brake Fluid
Your brake master cylinder
reservoir is here. It
is filled
with DOT-3 brake fluid.
There are only two reasons why the brake fluid level
in the
reservoir might go down. The first is that the brake fluid
goes down to an acceptable level during normal brake
lining wear. When new linings are put
in, the fluid level
goes back up. The other reason is that fluid
is leaking out
of the brake system. If it is, you should have your brake
system fixed, since
a leak means that sooner or later your
brakes won’t work well, or won’t work at
all.
So, it isn’t a good idea to “top off’ your brake fluid.
Adding brake fluid won’t correct a leak.
If you add fluid
when your linings are worn, then you’ll
have too much
fluid when
you get new brake linings. You should add
(or remove) brake fluid,
as necessary, only when work is
done
on the brake hydraulic system.
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4 CAU-ION:
If you have too much brake fluid, it can spill on the
engine. The fluid
will burn if the engine is hot
enough. You or others could be burned, and your
vehicle could be damaged. Add brake fluid only when
work is done on the brake hydraulic system.
Refer to the Maintenance Schedule to determine when to
check your brake fluid. See “Periodic Maintenance
Inspections” in the Index.
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NOTICE:
0
0
Using the wrong fluid can badly damage
brake system parts. For example, just a few
drops of mineral-based oil, such as engine
oil, in your brake system can damage brake
system parts
so badly that they’ll have to be
replaced. Don’t let someone put in the
wrong kind of fluid.
If you spill brake fluid on your vehicle’s
painted surfaces, the paint finish can be
damaged.
Be careful not to spill brake fluid
on your vehicle. If you do, wash it
off
immediately. See “Appearance Care” in
the Index.
Brake Wear
If you have a C 3500 HD model, it has four-wheel disc
brakes without wear indicators. If you ever hear
a brake
rubbing noise, have the brake linings inspected.
If your pickup is not a
C 3500 HD model, it has front
disc brakes and rear drum brakes. Disc brake pads
(except
C 3500 HD models) 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
The brake wear warning sound means that soon
your brakes won’t work well. That could lead to
an accident. When you hear the brake wear
warning sound, have your vehicle serviced.
I NOTICE:
Continuing to drive with worn-out brake pads
could result in costly brake repair.
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