1998 GMC SIERRA Owners Manual

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.
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NOTICE:
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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.
- - -
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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Checking Brake Fluid
You can check the brake fluid without taking off the cap.
Just look at the brake fluid reservoir. The fluid level
should be above
MIN. If it isn’t, have your brake system
checked to see if there is a leak.
After work
is done on the brake hydraulic system,
make sure the level is above the
MIN but not over the
MAX mark or the top
of the window on the side of
the reservoir. fluid
-- such
as Delco Supreme llw (GM Part
No. 12377967). Use new brake fluid from a sealed
container only.
Always clean the brake fluid reservoir cap and the area
around the cap before removing it. This will help keep
dirt from entering the reservoir.
A CAUTION:
I
With the wrong kind of fluid in your brake
system,
your brakes may not work well, or they
may not even work at all. This could cause a
crash. Always use the proper brake fluid.
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NOTICE:
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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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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.
Properly torqued wheel
nuts are necessary to help
prevent brake pulsation. When tires are rotated, inspect
brake pads for wear and evenly torque wheel nuts
in the
proper sequence to
GM specifications.
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 immediately. Also, the rear brake drums should be removed and
inspected each time the tires are removed for rotation
or
changing. When you have the front brake pads replaced,
have the rear brakes inspected, too.
Brake linings should always be replaced as complete
axle sets.
See “Brake System Inspection”
in Section 7 of this manual
under
Part C “Periodic Maintenance Inspections.”
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.
Brake Adjustment
Every time you make a brake stop, your disc brakes
adjust for wear.
If your brake pedal goes down farther than normal, your
rear drum brakes may need adjustment. Adjust them by
backing
up and firmly applying the brakes a few times.
Replacing Brake System Parts
The braking system on a modern vehicle is complex. Its
many parts have to be
of top quality and work well
together if the vehicle is to have really good braking.
Your vehicle was designed and tested
with top-quality
GM brake parts. When you replace parts of your braking
system
-- for example, when your brake linings wear
down and you have
to have new ones put in -- be sure
you get new approved
GM replacement parts. If you
don’t,
your brakes may no longer work properly. For
example,
if someone puts in brake linings that are wrong
for your vehicle, the balance between your front and
rear brakes can change
-- for the worse. The braking
performance you’ve come
to expect can change in many
other ways
if someone puts in the wrong replacement
brake parts.
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