1997 GMC JIMMY Owner's Manual

Front Axle
When to Check and Change Lubricant
Refer to the Maintenance Schedule to determine how
often to check the lubricant and when to change it. See
“Scheduled Maintenance Services” in the Index.
How to Check Lubricant
If the level is below the bottom of the filler plug hole,
you’ll need to add same lubricant.
If the differential is at operating temperature (warm),
add enough lubricant to raise the level to the bottom af
the filler plug hole.
If the differential is cold, add enough lubricant to raise
the level to 1/2 inch (12 mm) beluw 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.
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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
(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 DEX-COOL@ coolant
for your vehicle will:
Give freezing protection down to -34°F (-37°C).
0 Give boiling protection up to 265 OF ( 129 O C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning lights and gages work as
8
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.
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.
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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.
I 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
When your engine is cold. the coolant level should be at
ADD, or a little higher. When your engine is warm. the
level
should be up to FULL HOT, or a little higher.
Adding Coolant
If you need more coolant, add the proper DEX-COOL'
coolant mixture crt rhe cwolcrllt I-KO\!PI-J tcrnk.
~ ' 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 DEX-COOL@ 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
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
fronl overheating. Be sure the arrows
on the cap
line up with the overflow tube on the radiator
filler neck.
Thermostat
Engine coolant temperattrre 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.
Power Steerinp Fluid
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When to Check Power Steering Fluid
It is not necessary to regularly check power steering
fluid ~rnless
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 between the
ADD and FULL marks.
If necessary, add only enough fluid to bring the level up
to the proper range.
What to Use
Windshield Washer Fluid
What to Use
When you need windshield washer fluid. be sure to read
the manuf‘~cturer’s instructions before ~rse.
If you will be
operating your
\:chicle in an area where the temperature
may fall below freezing,
LIS~ a fluid that has sufficient
protection against freezing.
Adding Washer Fluid
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.
Open
the cap labeled WASHER FLUID ONLY with the
washer symbol 011 it. Add washer tluid 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.
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.
Fill your washer fluid tank only
Brakes
Brake Fluid
Y~LII. brake master cylinder reservoir is here. It is filled
with DOT-3 brake fluid.
6-28

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. Refer
to the Maintenance Schedule to determine when to
check your brake fluid. See “Periodic Maintenance
Inspections” in the Index.
Checking Brake Fluid
If you have too much brake fluid, it can spill on the
engine. The fluid
wiu 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.
I
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.
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