GMC SIERRA 1995 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 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.
The proper coolant for your vehicle will:
Give freezing protection down to -34°F (-37°C).
0 Give boiling protection up to 262°F (128°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning gages work as they should.
What to Use
Use a mixture of one-half cleun water (preferably distilled) and one-half
antifreeze that meets “GM Specification 6038-M,” which won’t damage
aluminum parts.
You can also use a recycled coolant conforming to “GM
Specification 6038-M.” Use GM Coolant Supplement (Sealer) with a
complete coolant flush and refill. 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
a proper antifreeze.
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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.
Some conditions. such as air trapped
in the cooling system. can affect the
coolant level
in thc radiator. Check the coolant level when the engine is cold
and
follow the steps under “Adding Coolant“ for the proper way to add
coolant.
If you have to add coolant more than lour timcs a ycar, 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.
Adding Coolant - Gasoline Engine
The coolant reco\wy
tank is located on the
passenger side
at the
rear comer
of the
engine compartment.
To Check Coolant
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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To Add Coolant
If you need more coolant, add the proper mix at the coolant recovery tank.
A CAUTION:
arning 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 mix 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.
Adding Coolani - Diesel Engine
The coolant surge tank
is located on the
passenger side at the
rear corner of the
engine compartment.
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To Check Coolant
A CAUTION:
Turning the surge tank pressure cap when the engine and
radiator are hot can allow steam and scalding liquids to blow out
and burn you badly. Never turn the surge tank pressure cap
-
even a little - when the engine and radiator are hot.
When your engine is cold, the coolant level should be at the COLD mark, or
a little higher.
If this light comes on, it means you’re low on engine coolant.
To Add Coolant
If you need more coolant, add the proper mix ut the surge tmk, but only
when the engine is cool. If the surge tank is empty, see “Engine
Overheating”
in the Index for the proper fill procedure.
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.
When replacing the pressure cap, make sure it is tight.
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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.
Surge Tank Pressure Cap - Diesel Engine
The surge tank
pressure cap must be
tightly installed with
the arrows on the cap
lined up with the top
tube of the coolant
surge tank.
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NOTICE:
Your surge tank pressure cap is a unique 15 psi (105 kPa)
pressure-type cap for use with surge tank cooling systems only.
It 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 top tube of the coolant surge tank.
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.
Power Steering Fluid
How To Check Power Steering Fluid
When the engine compartment is cool, 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 dips\
tick.
The level should be at the
FULL COLD mark. Add enough fluid to bring
the level
up to the mark.
A fluid loss in this system could indicate a problem. Have the system
inspected and repaired.
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What to Add
Refer to the Maintenance Schedule to determine what kind of' tluid to use
See "Recommended Fluids and Lubricants"
in the Index.
NOTICE:
When adding power steering fluid or making a complete fluid
change, always use the proper fluid. Failure to use
the proper
fluid can cause leaks and damage hoses and seals.
Hydro-Boost Brake System (Hydraulic Pump)
The power steering pump is also used as the Hydro-boost pump. Refer to
"Power Steering System''
in this section when checking fluid level or
adding fluid.
Windshield Washer Fluid
What to Use
When you need windshield washer fluid, be sure to read the manuhcturer'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.
To Add
Open the cap labeled
WASHER FLUID
ONLY. Add washer
fluid
until the tank is
full.
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~ NOTICE:
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.
0 Fill your washer fluid tank only 3/4 full when it’s very cold.
This allows for expansion, which could damage the tank if it
is
completely full.
0 Don’t use radiator antifreeze in your windshield washer. It
can damage your washer system and paint.
Brake Master Cylinder
Your brake master cylinder is here. It is filled with DOT-3 brake fluid.
There are only two reasons why the brake fluid level
in your master cylinder
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
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(or remove) brake fluid, as necessary, only when work is done on the brake
hydraulic system.
A CAUTION:
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.
To Check Brake Fluid
You can check the brake fluid without taking off the cap. Just look at the
windows on the brake fluid reservoir. The fluid levels should be above MIN.
If they aren’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 levels are
above MIN and below the top
of each window.
What to Add
When you do need brake fluid, use only DOT-3 brake fluid - such as
Delco Supreme 11
@ (GM Part No. 1052535). Use new brake fluid from a
sealed container only, and always clean the brake fluid reservoir cap before
removing it.
NOTICE:
Don’t let someone put in the wrong kind of fluid. 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.
Brake fluid can damage paint, so be careful not to spill brake
fluid on your vehicle.
If you do, wash it off immediately. See
“Appearance Care” in the Index.
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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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