1995 GMC SIERRA Owners Manual

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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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 modeffl VEShicle is complex. Its many parts have to
be of top quality and work well together if the vehicle
is to have really good
braking. Vehicles we design and test have top-quality
GM brake parts in
them, as your vehicle does when it is new. 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 genuine 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.
Front Shock Absorbers
The front shock absorbers of your vehicle do many things. They help the
vehicle ride smoothly and
also control the travel of the suspension system.
When the shock absorbers are serviced, any replacement shock absorbers
must be the same as the original equipment shock absorbers
in both
extended length and strength.
I NOTICE:
If you use shock absorbers that are not the same as the original
shock absorbers, the shock absorbers
or suspension system
could be damaged.
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Windshield Wiper Blade Inserts
To replace the
windshield wiper
blade insert, lift
the
wiper arm and rotate
the blade until
it is
facing away from the
windshield.
Unlatch the end
of the insert from the holding clips. Remove the insert and
slide
a new one in place. Make sure the blade is secured in the clips.
Air Conditioning
Every now and then have your dealership check your air conditioning
system to be sure it
has not lost any cooling ability. If you think the system
is not working properly, have your dealership check it out as soon as
possi bleb
The air conditioning will
not work when the temperature is below 40°F
(4°C).
Fluid Leak Check
After the vehicle has been parked for a while, inspect the surface under the
vehicle for water, oil, fuel
or other fluids. Water dripping from the air
conditioning system after it has been used is normal.
If you notice fuel leaks
or fumes, the causes should be found and corrected at once.
Lock Cylinders
To be sure your locks operate properly, they must be lubricated. Your
vehicle’s maintenance schedule will tell you how often to lubricate them.
See “Recommended Fluids and Lubricants” in the Index for
the proper
lubricant to use.
You should
not use penetrating oils because they could wash out the factory
installed lubricant and cause
the lock to bind. De-icers which contain
alcohol could also
wash away the lubricant, so be sure to lubricate the lock
after using
a de-icer of this type.
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