1998 GMC ENVOY engine

How to Check
Because this operation can be a little difficult, you
may choose to have this done at your
GM dealership
Service Department.
If you do it yourself, be sure
to follow all the
instructions here, or you could get
a false reading on
the dipstick.
NOTICE:
Too much or too little fluid can damage your
transmission.
Too much can mean that some of
the fluid could come out and fall on hot engine
parts or exhaust system parts, starting a fire.
Be
sure to get an accurate reading if you check your
transmission fluid.
Wait at least 30 minutes before checking the
transmission fluid level
if you have been driving:
When outside temperatures are above 90°F (32°C).
0 At high speed for quite a while.
0 In heavy traffic -- especially in hot weather.
While pulling a trailer.
To get the right reading, the fluid should be at
normal operating temperature, which is 180°F to
200°F
(82°C to 93°C). See “Checking Transmission Fluid
Hot”
in the Index.
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Checking Transmission Fluid Hot
Get the vehicle warmed up by driving about 15 miles
(24 km) when outside temperatures are above 50°F
(10°C). If it's colder than 50°F (lO"C), drive the
vehicle in THIRD (3) until the engine temperature gage
moves and
then remains steady for 10 minutes. Then
follow the hot check procedures.
Checking Transmission Fluid Cold
A cold check is made after the vehicle has been sitting
for eight hours or more with
the engine off and is used
only as
a reference. Let the engine run at idle for five
minutes
if outside temperatures are 50°F (10°C) or
more.
If it's colder than 50°F (lO"C), you may have to
idle the engine longer. Should the fluid level be low
during a cold check, you
1nust perform a hot check
before adding fluid. This will give you a more accurate
reading of the fluid level.
Checking the Fluid Hot or Cold
Park your vehicle on a level place. Keep the
engine running.
With the parking brake applied, place the shift lever
in PARK (P).
With your foot on the brake pedal, move the shift
lever through each gear range, pausing for about
three seconds in each range. Then, position the shift
lever
in PARK (P).
Let the engine run at idle for three minutes or more.
Then, without shutting
off the engine, follow these steps:
1. The transmission
dipstick has a red
handle and
is located at
the rear of the engine
compartment.
Flip the
handle up and then pull
out the dipstick and
wipe
it with a clean rag
or paper towel.
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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 may need to add some lubricant. When
the differential is cold, add enough lubricant to
raise the level to
1/2 inch (12 mm) below the filler
plug hole.
When the differential
is at operating temperature
(warm), add enough lubricant to raise the level
to the
bottom
of 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 s stem in your vehicle is filled with
DEX-COOL J 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.
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A 50/50 mixture of water and DEX-COOL@ coolant will:
0 Give freezing protection down to -34°F (-37°C).
Give boiling protection up to 265 “F ( 129°C).
0 Protect against rust and corrosion.
0 Help keep the proper engine temperature.
Let the warning lights and 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
0- 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.
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 mixture will. Your vehicle’s coolant
warning system is set for the proper coolant
mixture. With plain water or the wrong mixture,
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 mixture of clean water and
DEX-COOL@ coolant.
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NOTICE:
If you use an improper coolant mixture, your
engine could overheat and be badly damaged.
The repair cost wouldn’t be covered by your
warranty.
Too much water in the mixture 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.
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 at the cwolarzt recovery tank.
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-
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.
A CAUTION:
I
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.
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
from overheating. Be sure the arrows on the cap
line
up with the overflow tube on the radiator
filler neck.
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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.
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 between the
ADD and FULL marks.
If necessary, add only enough fluid to bring the level up
to the proper range.
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.
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Windshield Washer Fluid
What to Use
Open the cap labeled WASHER FLUID ONLY with
the washer symbol on
it. Add washer fluid until the tank
is full.
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.
Adding Washer Fluid
NOTICE:
0
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 engine coolant (antifreeze)
in
your windshield washer. It can damage
your washer system and paint.
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