
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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To Use the Engine Coolant Heater
1. Turn off the engine.
2. Open the hood and unwrap the electrical cord. The
cord is located on the driver’s side of the engine
compartment, behind the underhood fuse block.
3. Plug it into a normal, grounded 110-volt AC outlet.
% CAUTION:
Plugging the cord into an ungrounded outlet
could cause an electrical shock. Also, the wrong
kind
of extension cord could overheat and cause
a fire. You could be seriously injured. Plug the
cord into
a properly grounded three-prong
110-volt
AC outlet. If the cord won’t reach, use a
heavy-duty three-prong extension cord rated for
at least
15 amps.
4. Before starting the engine, be sure to unplug and
store the cord as it was before to keep it away from
moving engine parts. If you don’t, it could
be damaged.
How long should you keep the coolant heater plugged
in? The answer depends on the outside temperature, the
kind
of oil you have, and some other things. Instead of
trying to list everything here, we ask that you contact
your dealer in the area where you’ll be parking your
vehicle. The dealer can give you the best advice for that
particular area.
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NOTICE:
Driving with the parking brake on can cause
your rear brakes to overheat.
You may have to
replace them, and you could also damage other
parts of your vehicle.
If you are towing a trailer and you must park on a hill,
see “Towing
a Trailer” in the Index. That section shows
what to do first to keep the trailer from moving.
Shifting Into PARK (P)
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It can be dangerous to get out of your vehicle if
the shift lever is not fully in PARK (P) with the
parking brake
firmly set. Your vehicle can roll. If
you have left the engine running, the vehicle can
move suddenly. You or others could be injured.
To be sure your vehicle won’t move, even when
you’re on fairly level ground, use the steps that
follow. Always put the shift lever fully in
PARK
(P) with the parking brake firmly set. If
you’re pulling a trailer, see “Towing a Trailer” in
the Index.
1. Hold the brake pedal down with your right foot and
set the parking brake.
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2. Move the shift lever into PARK (P) position
like this:
Hold in the button on the lever.
Push the lever all the way toward the front of
the vehicle.
3. Turn the ignition key to LOCK,
4. Remove the key and take it with you. If you can
leave your vehicle with the key, your vehicle
is in
PARK
(P).
Leaving Your Vehicle With the
Engine Running
It can be dangerous to leave your vehicle with the
engine running. Your vehicle could move
suddenly if the shift lever is not fully in
PARK (P)
with the parking brake firmly set. And, if you
leave the vehicle with the engine running, it could
overheat and even catch fire. You or others could
be injured. Don’t leave your vehicle with the
engine running unless you have to.
If you have to leave your vehicle with the engine
running, be sure your vehicle is in PARK (P) and your
parking brake is firmly set before
you leave it. After
you’ve moved the shift lever into PARK
(P), hold the
regular brake pedal down. Then, see if you can move the
shift lever away from PARK
(P) without pressing the
button
on the shift lever. If you can, it means that the
shift lever wasn’t fully locked into PARK
(P).
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Anti-Lock Brake System Warning Light
With the anti-lock brake
system, this light will come
on when you start your
engine and may stay
on
for several seconds.
That’s normal.
If the light stays on, or comes on when you’re driving,
your vehicle needs service. If the regular brake system
warning light isn’t on,
you still have brakes, but you
don’t have anti-lock brakes. If the regular brake system
warning light is
also on, you don’t have anti-lock brakes
and there’s a problem with your regular brakes. See
“Brake System Warning Light” earlier
in this section.
The anti-lock brake system warning light should come
on briefly when you turn the ignition key to RUN. If the
light doesn’t come on then, have it fixed
so it will be
ready to warn you
if there is a problem.
Engine Coolant Temperature Gage
This gage shows the engine
coolant temperature. If the
gage pointer moves into
the
red area, your engine is
too hot!
It means that your engine coolant has overheated. If you
have been operating your vehicle under normal driving
conditions,
you should pull off the road, stop your
vehicle and turn off
the engine as soon as possible.
The “Problems on the Road” section
of this manual
shows you what to do. See “Engine Overheating”
in
the Index.
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Driving Downhill
When off-roading takes you uownhill, you'll want to
consider
a number of things:
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How steep is the downhill'? Will I be able to maintain
vehicle control?
What's the surface like'? Smooth'? Rough'? Slippery'?
Hard-packed dirt'? Gravel?
Are there hidden surface
obstacles'! Ruts?
Logs? Boulders'?
What's at the
bottom of the hill'! Is there a hidden
creek bank
or even a river bottom with large rocks?
If you decide you can go down a hill safely. then try to
keep your vehicle headed straight down. and use
a low
they won't have to do
all the work. Descend slowly,
keeping your vehicle under control at
all times.
b "ear. This way, engine drag can help your brakes and
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A CAUTION:
Heavy braking when going down a hill can cause
your brakes
to overheat and fade. This could
cause
loss of control and a serious accident.
Apply the brakes lightly when descending a hill
and use a low gear to keep vehicle speed
under control.
Are there some things
I should not do when
driving down a hill?
A: Yes! These are important because if you ignore
them you could lose control and have
a
serious accident.
When driving downhill, avoid turns that take you
across the incline of the
hill. A hill that's not too
steep to drive down may be too steep to drive ~CI-OSS.
You could roll over
if you don't drive straight down.
Never
go downhill with the transmission in
NEUTRAL (N). This is crdled "free-wheeling." Your
brakes
will have to do all the work and could
overheat and fade.
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Driving On Grades
Reduce speed and shift to a 1owe.r gear Iwfow you start
down a long or steep downgrade.
If you don’t shift
down. you might have to use your brakes
so much that
they would get hot and no longer work well.
On
a long uphill grade, shift down and reduce your
speed to around
45 mph (70 km/h) to reduce the
possibility of engine and transmission overheating.
You should use DRIVE
(D) when towing a trailer.
Operating your vehicle
in DRIVE (D) when towing a
trailer
will minimize heat buildup and extend the life of
your transmission.
When towing at high altitude
on steep uphill grades,
consider the following: Engine coolant
will boil at a lower
temperature than at normal altitudes.
If you twn your
engine off imnlediately after towing at high altitude on
steep uphill grades, your vehicle may show signs similar to
engine overheating.
To avoid this, let the engine run while
parked (preferably on level ground)
with the automatic
transmission
in PARK (PI for a few minutes before turning
the engine off.
If you do get the overheat warning. see
”Engine Overheating”
in the Index.
Parking on Hills
You really should not park your vehicle, with a trailer
attached.
on a hill. If‘ something goes wrong, your rig
could start
to move. People can be injured, and both
your vehicle and the trailer can be damaged.
But
if you ever have to park your rig on a hill, here‘s
how
to do it:
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Apply your regular brakes, but don’t shift into
PARK
(P) yet. Then turn your wheels into the curb
if facing downhill or into traffic if facing uphill.
Have someone place chocks under the trailer wheels.
When the wheel chocks are
in place, release the
regular brakes
until the chocks absorb the load.
Reapply the regular brakes. Then apply your parking
brake, and then shift into PARK
(P).
Release the regular brakes.
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Section 5 Problems on the Road
Here you’ll find what to do about some problems that can occur on the road.
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Hazard Warning Flashers
Other Warning Devices
Jump Starting
Towing
Your Vehicle
Engine Overheating Engine
Fan Noise
If a Tire Goes Flat
Changing a Flat Tire
If You’re Stuck: In Sand, Mud,
Ice or Snow
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