1997 GMC SIERRA Owners Manual

If the differential is at operating temperature (warm),
add enough lubricant to raise the level to the bottom of
the filler plug hole.
If the differential is cold, add enough lubricant to raise
the level to 1/2 inch (12 mm) below 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 system in your vehicle is filled with
new DEX-COOL@ engine coolant. This coolant is
designed to remain in your vehicle for
5 years or
150,000 miles (240
000 km), whichever occurs first,
if
you add only DEX-COOL@ extended life coolant.
The following explains your cooling system and how to
add coolant when
it is low. If you have a problem with
engine overheating, see “Engine Overheating” in
the Index.
A 50/50 mixture of water and the proper coolant for
your vehicle will:
0 Give freezing protection down to -34°F (-37°C).
0 Give boiling protection up to 265 “F (1 29°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
0 Let the warning gages work as they should.
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.
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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.
A 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
mix will. Your vehicle’s coolant warning
system is set for the proper coolant
mix. With
plain water or the wrong
mix, 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 mix of clean
water and
DEX-COOL@ coolant.
NOTICE:
If you use an improper coolant mix, your engine
could overheat and be badly damaged. The
repair cost wouldn’t be covered
by your
warranty. Too much water in the mix 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.
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Checking Coolant
If your vehicle has a diesel engine, see “Checking
Coolant”
in the Diesel Engine Supplement. Adding Coolant
If you need more
coolant, add the proper DEX-COOL@
coolant mixture
at the coolant recovery tank.
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.
A CAUTION:
Turning 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.
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.
Failure to use the proper fluid can cause leaks and
damage hoses and seals.
Windshield Washer Fluid
What to Use
When you 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
fall 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.
NOTICE:
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 radiator 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.
I
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 window on 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
MIN and below the top of
the window.
What to Add
When you do need brake fluid, use only DOT-3 brake
fluid
-- such as Delco Supreme ll@ (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:
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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