ESP GMC SIERRA 1998 User Guide

Scanning the Terrain
Off-road driving can take you over many different kinds
of terrain. You need to
be familiar with the terrain and its
many different features. Here are some things to consider.
Su$ace Conditions. Off-roading can take you over
hard-packed dirt, gravel, rocks, grass, sand, mud, snow or
ice. Each
of these surfaces affects the steering, acceleration
and braking of your vehicle in different ways. Depending
upon the kind of surface
you are on, you may experience
slipping, sliding, wheel spinning, delayed acceleration,
poor traction and longer braking distances.
Su$ace Obstacles. 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:
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
surface 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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steering, suspension, wheels, tires ana exhaust system
for damage.
Also, check the fuel lines and cooling
system for any leakage. 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.
Your vehicle will require more frequent service due to
off-road use. Refer
to the Maintenance Schedule for
additional information.
Driving at Night
Here are some tips on night driving.
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Drive defensively.
Don’t drink and drive.
Adjust your inside rearview mirror
to reauce me
glare from headlamps behind you.
Since you can’t see as well,
you may need to
slow down and keep more space between you and
other vehicles.
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.
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J L
Wet brakes can cause accidents. They won’t work
as well in a quick stop and may cause pulling to
one side. You could lose control
of the vehicle.
After driving through
a large puddle of water or
a car wash, apply your brake pedal lightly until
your brakes work normally.
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 fast rule about hydroplaning. The
best advice
is to slow down when it is raining.
Driving Through Deep Standing Water
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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 careful when you pass
another vehicle. Allow yourself more clear room
ahead, and be prepared to have your view restricted
by road spray.
0 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 (or batteries) charged. You will need a
well-charged battery
(or batteries) to restart the vehicle,
and possibly for signaling later on with your headlamps.
Let the heater run for a while.
If you have a diesel engine, you may have to run it at a
higher speed to get enough heat. 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.
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NOTICE:
Some vehicles may be equipped with RPO VYU
(snow plow prep package). With this option, the
payload your vehicle can carry is reduced when
a
snow plow is installed. Your vehicle can be
damaged if either the front or rear axle ratings,
or the GVW are exceeded.
As a general guideline, with a 650 Ib. (295 kg)
snow plow, the weight of the occupants and cargo
must not exceed
300 lb. (135 kg). However, this
may depend on the vehicle's option content.
Therefore, to help avoid vehicle damage:
0 Make sure the weight on the front and
rear axles does not exceed their respective
axle ratings.
GVW rating.
Total vehicle weight must not exceed the
NOTICE: (Continued)
I NOTICE: (Continued) I
If more cargo or passengers need to be
carried, appropriate counter ballast must
be installed rear of the rear axle and
properly secured.
0 See your dealer for advice and information
about using
a snow plow on your vehicle.
Do not load your vehicle any heavier than the
GVWR, or either the maximum front or rear
GAWR.
If' you do, parts on your vehicle can break,
or it can change the
way your vehicle handles.
These could cause you to lose control.
Also,
overloading can shorten the life of your vehicle.
Using heavier suspension components to get added
durability might not change your weight ratings.
Ask
your dealer to help you load your vehicle the right way.
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Safety Chains
You should always attach chains between your vehicle
and your trailer. Cross the safety chains under the tongue
of the trailer so that’the tongue will not drop to the road
if it becomes separated from the hitch. Instructions
about safety chains may be provided by the hitch
manufacturer or by the trailer manufacturer. Follow the
manufacturer’s recommendation for attaching safety
chains and do not attach them to the bumper. Always
leave just enough slack
so you can turn with your rig.
And, never allow safety chains
to drag on the ground.
Trailer Brakes
If your trailer weighs more than 1,000 Ibs. (450 kg)
loaded, then it needs its own brakes
-- and they must be
adequate. Be sure to read and follow the instructions for
the trailer brakes so you’ll be able to install, adjust and
maintain them properly.
Your trailer brake system can tap into the vehicle’s
hydraulic brake system only if
0 The trailer parts can withstand 3,000 psi
(20 650 kPa) of pressure.
0 The trailer’s brake system will use less than
0.02 cubic inch (0.3 cc) of fluid from your vehicle’s
master cylinder. Otherwise, both braking systems
won’t work well. You could even lose your brakes.
If everything checks out this far, make the brake tap at
the port
on the master cylinder that sends the fluid to the
rear brakes.
But don’t use copper tubing for this. If you
do,
it will bend and finally break off. Use steel
brake tubing.
Driving with a Trailer
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 are
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.
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5. If you have a four-wheel-drive vehicle,
be sure the transfer case is in
a drive gear and not
in
NEUTRAL (N).
6. Release the regular brakes.
-
/r CAUTIOIA:
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.
If you have four-wheel drive and your transfer
case is in
NEUTRAL (N), your vehicle will be free
to
roll, even if your shift lever is in PARK (P). So,
be sure the transfer case is in a drive gear -- not
in
NEUTRAL (N).
When You Are Ready to Leave After
Parking
on a Hill
1. Apply your regular brakes and hold the pedal down
while you:
Start your engine;
Shift into a gear; and
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 If a Tire Goes Flat
Your 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 fan is spinning slower and the clutch
is
not fully engaged. This improves fuel economy and
reduces fan noise. Under heavy vehicle loading. trailer
towing and/or high outside temperatures, the fan speed
increases as the clutch more
fully 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
partially disengages. 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 hils, 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
jacking equipment to change a flat tire safely.
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Automatic Transmission Fluid
If your vehicle has a diesel engine, see “Automatic
Transmission Fluid”
in the Diesel Supplement.
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
50,000 miles
(83
000 km) if the vehicle’s GVWR is over 8,600 or
if the vehicle is mainly driven under one or more of
these conditions:
In heavy city traffic where the outside temperature
In hilly or mountainous terrain.
When doing frequent trailer towing.
Uses such as found in taxi, police or delivery service.
regularly
reaches
90°F (32°C) or higher.
If your vehicle’s GVWR is not over 8,600 and you do not
use your vehicle under any
of these conditions, change the
fluid and filter every
100,000 miles (166 000 km).
See “Scheduled Maintenance Services’’ in the Index.
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).
At high speed for quite a while.
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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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.
io dd 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). Don’t overfill.
I 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-111
is not covered by your new vehicle warranty.
After adding fluid, recheck the fluid level as
described under “How to Check.”
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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