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The 1998 GMC Envoy Owner’s Manual
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Seats and Restraint Systems
This section tells you how to use your seats and safe.ty belts properly. It also explains the “SIR” system.
Features and Controls
This section explains how to start and operate your vehicle.
Comfort Controls and Audio Systems
This section tells you how to adjust the ventilation and comf‘orr controls and how to operate your audio system.
Your Driving and the Road
Here you’ll find helpful information and tips about. the road and how to drive under different conditions.
Problems on the Road
This section tells what to do if you have a problem while driving, such as a flat tire or overheated engine, etc.
Service and Appearance Care
Here the manual tells you how to keep your vehicle running properly and looking good.
Maintenance Schedule
This section tells you when to perform vehicle maintenance and what fluids and lubricants to use.
Customer Assistance Information
This section tells you how to contact GMC for assistance and how to get service and owner publications.
It also gives you information on “Reporting Safety Defects” on page 8- 10.
Index
Heree‘s an alphabetical listing of almost every subject in this manual. You can use it to quickly find
something you want to read.
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Your vehicle will require more frequent service due to
off-road use. Refer to the Maintenance Schedule for
additional information.
Drivin at Night
Night driving is more dangerous than day driving. One
reason is that some drivers are likely to be
impaired
-- by alcohol or drugs, with night vision
problems. or by fatigue. Here
are some tips on night driving.
0 Drive defensively.
0 Don't drink and drive.
0 Adjust your inside rearview mirror to reduce the
0 Since you can't see as well, you may need to slow
c2 "lare from headlamps behind you.
down and keep more space between
you and
other vehicles.
0 Slow down, especially on higher speed roads. Your
headlamps can light up only
so much road ahead.
In remote areas, watch for animals.
If you're tired. pull off the road in a safe place
and rest.
Night Vision
No one can see as well at night as in the daytime. But as
we get older these differences increase.
A 50-year-old
driver may require at least twice as much light to
see the
same thing
at night as a 20-year-old.
What you do
in the daytime can also affect your night
vision. For example,
if you spend the day in bright
sunshine
you are wise to wear sunglasses. Your eyes will
have
less trouble adjusting to night. But if you're
driving,
don't wear sunglasses at night. They may cut
down on glare from headlamps, but they also make a lot
of things invisible.
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When You Are Ready to Leave After
Parking on a Hill
1. Apply your regular brakes and hold the pedal down
while you:
0 Start your engine;
Shift into a gear; and
0 Release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the chocks.
Maintenance When Trailer Towing
Your vehicle will need service more often when you’re
pulling
a trailer. See the Maintenance Schedule for more
on this. Things that are especially important in trailer
operation are automatic transmission fluid (don’t
overfill), engine
oil, axle lubricant, belt, cooling system
and brake adjustment. Each of these is covered in this
manual, and the Index will help you find them quickly.
If you’re trailering, it’s
a good idea to review these
sections before you start your trip.
Check periodically to see that all hitch nuts and bolts
are tight.
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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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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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2. Push it back in all the way, wait three seconds and
then pull it back
out again.
3. Check both sides of the dipstick, and read the lower
level. The fluid level must be in the COLD area for a
cold check or in the
HOT area or cross-hatched area
for a hot check.
4. If the fluid level is in the acceptable range, push the
dipstick back in all the way; then flip the handle
down to lock the dipstick in place.
How to Add Fluid
Refer to the Maintenance Schedule to determine what
kind of transmission fluid to
use. See “Recommended
Fluids and Lubricants” in the Index.
Add fluid only after checking the transmission fluid
while it is hot.
(A cold check is used only as a
reference.) If the fluid level is low, add only enough
of the proper fluid to bring the level
up to the HOT
area for a hot check. It doesn’t take much fluid,
generally less than one pint
(0.5 L). Dun ’t overfiill.
NOTICE:
We recommend you use only fluid labeled
DEXRON@-111, because fluid with that label is
made especially for your automatic transmission.
Damage caused by fluid other than DEXRON-I11
is not covered by your new vehicle warranty.
0 After adding fluid, recheck the fluid level as
described under
“How to Check.”
0 When the correct fluid level is obtained, push the
dipstick back in all the way; then flip
the handle
down to lock the dipstick in place.
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Rear 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 some lubricant. 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.
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Four-wheel Drive
Transfer Case
When to Check Lubricant
Refer to the Maintenance Schedule to determine how
often
to check the lubricant. See “Periodic Maintenance
Inspections” in
the Index.
How to Check Lubricant
If the level is below the bottom of the filler plug hole,
you’ll need to add some lubricant. Add enough lubricant
to raise
the level to the bottom of the filler plug hole.
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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