ESP GMC ENVOY 1998 User Guide

Traveling to Remote Areas
It makes sense to plan your trip, especially when going
to
a remote area. Know the terrain and plan your route.
You are much less likely to get bad surprises. Get
accurate maps of trails and terrain. Try to learn of any
blocked
or closed roads.
It’s also a good idea to travel with at least one other
vehicle.
If something happens to one of them, the other
can help quickly.
Getting Familiar with Off-Road Driving
It’s a good idea to practice in an area that’s safe and
close
to home before you go into the wilderness.
Off-road driving does require some new and different
driving skills. Here’s what we mean.
Tune your senses to different kinds of signals. Your
eyes, for example, need to constantly sweep the terrain
for unexpected obstacles. Your ears need to listen for
unusual tire or engine sounds. With your arms, hands,
feet and body.
you‘ll need to respond to vibrations and
vehicle bounce. Controlling
your vehicle is the
key to successful
off-road driving. One
of the best ways to control your
vehicle is
to control your speed. Here are some things to
keep
in mind. At higher speeds:
0 you approach things faster and you have less time to
scan the terrain for obstacles.
0 you have less time to react.
0 you have more vehicle bounce when you drive
over obstacles.
0 you’ll need more distance for braking, especially
since you’re on an unpaved surface.
A c. u7c-i:
When you’re driving off-road, bouncing and
quick changes in direction can easily throw you
out of position. This could cause you
to lose
control and crash.
So, whether you’re driving on
or off the road, you and your passengers should
wear safety belts.
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Scanning the Terrain
Off-road driving can take you over many different kinds
of terrain.
You need to be familiar with the telrain and its
many different features. Here are some things to consider.
S~lr$uce Conditions. Off-roading can take you over
hard-packed dirt, gravel, rocks, grass, sand, mud, snow
or ice. Each of these surfaces affects the steering,
acceleration and braking of your vehicle
in different
ways. Depending upon the kind of surface
you are on,
you may experience slipping, sliding, wheel spinning,
delayed acceleration, poor traction and longer
braking distances.
Su$ace Obstucles . Unseen or hidden obstacles can be
hazardous.
A rock, log, hole, rut or bump can startle you if
you're not prepared for them. Often these obstacles are
hidden by grass, bushes, snow
or even the rise and fall of
the terrain itself. Here are
some things to consider:
0 Is the path ahead clear'?
Will the surface texture change abruptly up ahead?
Does the travel take you uphill or downhill? (There's
more discussion of these subjects later.)
Will you have to stop suddenly or change
direction quickly'? When you
drive over obstacles or rough terrain, keep
a
firm grip on the steering wheel. Ruts, troughs or other
surhce features can jerk the wheel out
of your hands if
you're not prepared.
When you drive over bumps, rocks, or other obstacles,
your wheels can leave the ground.
If this happens, even
with one or two wheels, you can't control the vehicle as
well or at all.
Because you
will be on an unpaved surface, it's
especially important to avoid sudden acceleration,
sudden turns or sudden braking.
In a way, off-road driving requires a different kind of
alertness from driving on paved roads and highways.
There are no road signs, posted speed limits or signal
lights.
You have to use your own good judgment about
what is safe and what isn't.
Drinking and driving can be very dangerous
on any
road. And this is certainly true for off-road driving. At
the very time
you need special alertness and driving
skills, your reflexes, perceptions and judgment can be
affected by even
a small amount of alcohol. You could
have a serious
-- or even fatal -- accident if you drink
and drive or ride with a driver who has been drinking.
See "Drunken Driving"
in the Index.
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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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Hydroplaning
Hydroplaning is dangerous. So much water can build up
under your tires that they can actually ride on the water.
This can happen
if the road is wet enough and you’re
going fast enough. When your vehicle is hydroplaning,
it has little or no contact with the road.
Hydroplaning doesn‘t happen often.
But it can if your
tires do not have much tread
or if the pressure in one or
more
is low. It can happen if a lot of water is standing on
the road. If you can see reflections from trees, telephone
poles or other vehicles, and raindrops ”dimple” the
water‘s surface, there could be hydroplaning.
Hydroplaning usually happens at higher speeds. There
just isn’t a hard and fdst rule about hydroplaning. The
best advice
is to slow down when it is raining.
1 )riving Through Deep Standing W ’ Fr
NOTICE:
If you drive too quickly through deep puddles or
standing water, water can come in through your
engine’s air intake and badly damage your
engine. Never drive through water that
is slightly
lower than the underbody
of your vehicle. If’ you
can’t avoid deep puddles or standing water, drive
through them very slowly.
Some Other Rainy Weather Tips
0 Besides slowing down, allow some extra following
distance.
And be especially carefir1 when you pass
another vehicle. Allow yourself more clear room
ahead, and be prepared
to have your view restricted
by road spray.
Have good tires with proper tread depth. (See
“Tires”
in the Index.)
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Snow can trap exhaust gases under your vehicle.
This can cause
deadly CO (carbon monoxide) gas
to get inside. CO could overcome
you and kill
you. You can’t see it
or smell it, so you might not
know it
is in your vehicle. Clear away snow from
around the base
of your vehicle, especially any
that is blocking your exhaust pipe. And check
around again from time to time to be sure snow
doesn’t collect there.
Open a window just
a little on the side of the
vehicle that’s away from the wind. This will help
keep
CO out.
Run your engine only as long as you must. This saves
fuel. When you
run the engine. make it go a little faster
than just idle. That is. push the accelerator slightly. This
uses less fuel for the heat that you get and
it keeps the
battery charged.
YOLI will need a well-charged battery to
restart the vehicle, and possibly for signaling later
on
with your headlamps. Let the heater run for a while.
Then, shut the engine off and close the window almost
all the way to preserve the heat. Start the engine again
and repeat this only when you feel really uncomfortable
from the cold.
But do it as little as possible. Preserve the
fuel
as long as you can. To help keep warm, you can get
out of the vehicle and do some fairly vigorous exercises
every half hour or
so until help comes.
Recreational Vehicle Towing
Vehicles with the electronic shift transfer case require
special modifications before they can be towed
in this
manner. Please contact your dealer
.for the towing
information that is appropriate
for yoc~r
particular vehicle.
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Driving with a Trailer
A CAUTION: I
0
0
0
If you have a rear-most window open and you
pull a trailer with your vehicle, carbon monoxide
(CO) could come into your vehicle. You can’t see
or smell
CO. It can cause unconsciousness or
death. (See ‘(Engine Exhaust” in the Index.) To
maximize your safety when towing a trailer:
Have your exhaust system inspected for
leaks, and make necessary repairs before
starting on your trip.
Keep the rear-most windows closed.
If exhaust does come into your vehicle
through a window in the rear or another
opening, drive with your front, main
heating or cooling system on and with the
fan on any speed. This will bring fresh,
outside air into your vehicle.
Do not use
RECIRCULATION because it only
recirculates the air inside your vehicle. (See
“Comfort Controls” in the Index.)
Towing a trailer requires a certain amount of experience, ~
Before setting out for the open road, you’ll want to get
to know your rig. Acquaint yourself with the feel of
handling and braking with the added weight of the
trailer. And always keep in mind that the vehicle you
arc
driving is now a good deal longer and not nearly as
responsive as your vehicle is by itself.
Before you
start, check the trailer hitch and platform
(and attachments), safety chains, electrical connector,
lamps, tires and mirror adjustment. If the trailer has
electric brakes, start your vehicle and trailer moving and
then apply the trailer brake controller by hand to be sure
the brakes are working. This lets you check your
electrical connection at the same time.
During your trip, check occasionally to
be sure that the
load is secure, and that the lamps and any trailer brakes
are still working.
Following Distance
Stay at least twice as far behind the vehicle ahead as you 1
would when driving your vehicle without a trailer. This
can help you avoid situations that require heavy braking
and sudden turns.
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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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Engine Fan Noise
This vehicle has a clutched engine cooling fan. When the
clutch is engaged, the fan spins faster to provide more air
to cool the engine. In most everyday driving conditions,
the clutch is
not engaged. This improves fuel economy and
reduces
fan noise. Under heavy vehicle loading, trailer
towing and/or high outside temperatures, the fan speed
increases when the clutch engages.
So you may hear an
increase in fan noise. This is normal and should not be
mistaken
as the transmission slipping or making extra
shifts. It is merely the cooling system functioning properly.
The fan will slow down when additional cooling is not
required and the clutch disengages.
You may
also hear this fan noise when you start the
engine. It will go away
as the fan clutch disengages.
If a Tire Goes Flat
It’s unusual for a tire to “blow out” while you’re driving,
especially if you maintain your tires properly.
If air goes
out of
a tire, it’s much more likely to leak out slowly.
But
if you should ever have a “blowout,” here are a few
tips about what to expect and what to do:
If
a front tire fails, the flat tire will create a drag that
pulls the vehicle toward that side.
Take your foot off the
accelerator pedal and grip
the steering wheel firmly.
Steer to maintain lane position, and then gently brake to
a stop well out of the traffic lane.
A rear blowout, particularly on a curve, acts much like a
skid and may require the same correction you’d use in a
skid. In any rear blowout, remove your foot from the
accelerator pedal. Get the vehicle under control by
steering the
way you want the vehicle to go. It may be
very bumpy and noisy, but you can
still steer. Gently
brake to
a stop -- well off the road if possible.
If a tire goes flat, the next part shows how to use your
iacking equipment to change
a flat tire safely. u Y a. c
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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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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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