1998 GMC ENVOY oil change

Have you recently changed brands of fuel?
If so, be sure to fuel your vehicle with quality fuel (see
"Fuel"
in the Index). Poor fuel quality will cause your
engine not to run as efficiently
as designed. You may
notice this as stalling after start-up, stalling when you
put the vehicle into gar, misfiring, hesitation on
acceleration or stumbling on acceleration. (These
conditions may go away once the engine
is warmed up.)
This will be detected by the system and cause the light
to turn on.
If you experience one or more of these conditions,
change the
fuel brand you use. It will require at least one
full tank of the proper fuel to turn the light off.
If none of the above steps have made the light turn off,
have your dealer or qualified service center check the
vehicle. Your dealer has the proper test equipment and
diagnostic tools to
fix any mechanical or electrical
problems that may have developed.
Engine Oil Pressure Gage
The oil pressure gage shows
the engine
oil pressure in
psi (pounds per square inch)
when the engine is running.
Canadian vehicles indicate pressure
in kPa (kilopascals).
Oil pressure may vary with engine speed, outside
temperature and oil viscosity, but readings above the
low pressure zone indicate the normal operating range.
A reading in the low pressure zone may be caused by a
dangerously low
oil level or other problems causing low
oil pressure.
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What Kind of Eng 3il to Use
Oils recommended for your vehicle can be identified by
looking for the “Starburst” symbol. This symbol
indicates that the oil has been certified by the American
Petroleum Institute (API).
Do not use any oil which
does not carry this Starburst symbol.
If you change your own oil,
be sure you use oil that has
the Starburst symbol on the
front of the
oil container. If
you have your oil changed
for you, be sure the oil
put
into your engine is
American Petroleum
Institute certified
for
gasoline engines.
You should also use the proper viscosity oil for your
vehicle, as shown in the following chart:
I RECOMMENDED SA€ VISCOSITY GRADE ENGINE OILS
FOR BEST FUEL ECONOMY AND COLD STARTING, SELECT THE LOWEST
I SAL VISCOSITY GRADE OIL FOR THE EXPECTED TEMPERATURE RANGE.
L
HOT
WEATHER
+ 20 7
SAE SW-30 PREFERRED
LOOK
FOR MIS
SYMBOL
00 NOT USE SAE 2OW-50 OR ANY OTHER
GRADE OIL NOT RECOMMENDED
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As shown in the chart, SAE SW-30 is best for your
vehicle. However, you can use
SAE low-30 if it’s going
to be 0°F (- 18°C) or above. These numbers on an oil
container show its viscosity, or thickness. Do
not use
other viscosity oils, such
as SAE 20W-SO.
NOTICE:
Use only engine oil with the American Petroleum
Institute Certified For Gasoline Engines
“Starburst”
symbol. Failure to use the
recommended oil can result in engine damage not
covered by your warranty.
GM Goodwrench@ oil meets all the requirements for
your vehicle.
If you are in an area where the temperature falls below
-20°F (-29”C), consider using either an SAE 5W-30
synthetic oil or an SAE OW-30 oil. Both will provide
easier cold starting and better protection for your engine
at extremely low temperatures.
Engine Oil Additives
Don’t add anything to your oil. Your dealer is ready to
advise if you think something should be added.
When to Change Engine Oil
If any one of these is true for you, use the short tripkity
maintenance schedule:
0 Most trips are less than 5 to 10 miles (8 to 16 km).
This is particularly important when outside
temperatures are below freezing.
driving
in stop-and-go traffic).
off-road frequently. your vehicle.
or other commercial application.
0 Most trips include extensive idling (such as frequent
0 You operate your vehicle in dusty areas or
0 You frequently tow a trailer or use a carrier on top of
0 The vehicle is used for delivery service, police, taxi
Driving under these conditions causes engine oil
to
break down sooner. If any one of these is true for your
vehicle, then you need to change your
oil and filter
every
3,000 miles (5 000 km) or 3 months -- whichever
occurs first.
If none of them is true, use the long trip/highway
maintenance schedule. Change the oil and filter every
7,500 miles (12 500 km) or 12 months -- whichever
occurs first. Driving
a vehicle with a fully warmed
engine under highway conditions causes engine oil
to
break down slower.
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Remote Oil Filter
The access door for the remote oil filter is in the steering
linkage shield assembly located under the radiator
support. Twist the screw to unlock or lock the door.
If
you open the door, make sure it is securely closed when
you are finished.
What to Do with Used Oil
Did you know that used engine oil contains certain
elements
that may be unhealthy for your skin and could
even cause cancer? Don’t let used oil stay on your skin
for very long. Clean your skin and nails with soap and
water, or
a good hand cleaner. Wash or properly throw
away clothing or rags containing used engine oil. (See
the manufacturer’s warnings about the use and disposal
of oil products.)
Used oil can be a real threat to the environment. If you
change your own oil, be sure to drain all free-flowing oil
from the filter before disposal. Don’t ever dispose of oil
by putting
it in the trash, pouring it on the ground, into
sewers, or into streams or bodies
of water. Instead,
recycle it by taking it to
a place that collects used oil. If
you have a problem properly disposing of your used oil,
ask your dealer, a service station or a local recycling
center for help.
To remove the air cleaner, remove the wing nuts that
hold the cover on. Remove the cover and lift
out the
air filter.
Insert
a new air filter, then replace the air cleaner cover.
Tighten the wing nuts
to hold the cover in place.
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A CAUTION:
Operating the engine with the air cleaner off can
cause you or others to be burned. The air cleaner
not only cleans the air, it stops flame
if the engine
backfires.
If it isn’t there, and the engine
backfires, you could be burned. Don’t drive with
it
off, and be careful working on the engine with
the
air cleaner off.
NOTICE:
If the air cleaner is off, a backfire can cause a
damaging engine fire. And, dirt can easily get
into your engine, which will damage it. Always
have the air cleaner in place when you’re driving.
Automatic Transmission Fluid
When to Check and Change
A good time to check your automatic transmission fluid
level
is when the engine oil is changed.
Change both the fluid and filter every
15,000 miles
(25 000 km) if the vehicle is mainly driven under one
or more of these conditions:
In heavy city traffic where the outside temperature
regularly reaches
90°F (32°C) or higher.
In hilly or mountainous terrain.
When doing frequent trailer towing.
Uses such as found in taxi, police or delivery service.
If you do not use your vehicle under any of these
conditions, change the fluid and filter every
50,000 miles (83 000 km).
See “Scheduled Maintenance Services’’ 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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Cleaning the Inside of Your Vehicle
Use a vacuum cleaner often to get rid of dust and loose
dirt. Wipe vinyl, leather, plastic and painted surfxes
with a clean, damp cloth.
Your dealer has two cleaners, Multi-Purpose Interior
Cleaner and Capture Non-Solvent Dry Spot and
Soil
Remover for cleaning fabric and carpet. They will clean
normal spots and stains very well. You can get
GM-approved cleaning products from your dealer. (See
“Appearance Care and Materials”
in the Index.)
Here are some cleaning tips:
Always read the instructions on the cleaner label.
Clean up stains as soon as you can -- before they set.
0 Carefully scrape off any excess stain.
Use a clean cloth or sponge, and change to a clean
area often.
A soft brush may be used if stains
are stubborn.
0 If a ring forms after spot cleaning, clean the entire
area immediately or
it will set.
Using Multi-Purpose Interior Cleaner
on Fabric
1. Vdcuum and brush the area to remove any loose dirt.
2. Always clean a whole trim panel or section. Mask
surrounding trim along stitch or welt lines.
3. Mix powdered cleaner following the directions on
the container label to form thick suds.
4. Use suds only and apply with a clean sponge. Don’t
saturate the material and don’t rub
it roughly.
5. As soon as you’ve cleaned the section, use a sponge
to remove the suds.
6. Wipe cleaned area with a clean, damp towel or cloth.
7. Wipe with a clean cloth and let dry.
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Normal Maintenance Replacement Parts
Replacement part numbers listed in this section are
based on the latest information available at the time of
printing, and are subject
to change. If a part listed in this
manual is not the same as the part used in your vehicle
when it was built, or if you have any questions, please
contact your GMC dealer.
Thermostat
......................... 1255905 1
Oil Filter ............................... PF52
Air Cleaner Filter
...................... A1 163C
PCV Valve
.......................... CV746C
Automatic Transmission Filter Kit
...... 24200796
Spark Plugs
.......................... .41-932
Fuel Filter
............................. GF48 1
Front Windshield Wiper Blade
................ Trico (20 inched50.8 cm)
Backglass Wiper Blade . . Trico (14 inched35.6 cm)
Capacities (Approximate)
Cooling System* ............. 11.7 quarts (1 1.1 L)
Crankcase* ................... 4.5 quarts (4.3 L)
Automatic Transmission
(Drain and Refill)*
........... 5.0 quarts (4.7 L)
Differential Fluid ............................
Front ....................... 2.6 pints (1.2 L)
Rear ........................ 4.0 pints ( 1.9 L)
Fuel Tank ..................... 18 gallons (68 L)
A/C Refrigerant ........... 30 oz. or 2 lbs. (0.9 kg)
of R- 134a
*After refill, the level
must be checked.
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