traction control GMC SONOMA 1999 Owner's Manual

Table of Contents (cont'd)
Braking/Anti-lock Brakes (If Equipped)
Traction Control System
Steering
Driving Tips for Various Road ConditionsOff-Road Driving
Recreational Vehicle Towing
Loading Your Vehicle
Towing a Trailer Heating and Air Conditioning
Setting the Radio Clock
Radio/Cassette Player/CD PlayerRadio Theft-Deterrent Feature
Steering Wheel Controls (If Equipped)
Hazard Warning Flashers
Jump Starting
Towing Your VehicleEngine Overheating
Changing a Flat Tire
If You're Stuck
Problems on the Road
Section
3
Section
4
Section
5
Your Driving and the Road Comfort Controls and Audio Systems
iii

2-23 Shift Light
If you have a manual
transmission, you have a
SHIFT light.
This light will show you when to shift to the next higher
gear for best fuel economy.
When this light comes on, you can shift to the next
higher gear if weather, road and traffic conditions let
you. For the best fuel economy, accelerate slowly and
shift when the light comes on.
While you accelerate, it is normal for the light to go on
and off if you quickly change the position of the
accelerator. Ignore the SHIFT light when you downshift.
CAUTION:
If you skip a gear when you downshift, you could
lose control of your vehicle. You could injure
yourself or others. Don't shift down more than
one gear at a time when you downshift.
Four-Wheel Drive (If Equipped)
If your vehicle has four-wheel drive, you can send your
engine's driving power to all four wheels for extra
traction. To get the most satisfaction out of four
-wheel
drive, you must be familiar with its operation. Read the
part that follows before using four
-wheel drive. You
should use two
-wheel drive (2HI) for most normal
driving conditions.
NOTICE:
Driving in the 4HI or 4LO positions for a long
time on dry or wet pavement could shorten the
life of your vehicle's drivetrain.

2-32
CAUTION:
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.
Don't leave your vehicle when the engine is
running unless you have to. If you've 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, always set your parking brake and
move the shift lever to PARK (P).
Follow the proper steps to be sure your vehicle won't
move. See ªShifting Into PARK (P)º in the Index.
If you're pulling a trailer, see ªTowing a Trailerº in
the Index.
Locking Rear Axle
If your vehicle has this feature, your locking rear axle
can give you additional traction on snow, mud, ice, sand
or gravel. It works like a standard axle most of the time,
but when one of the rear wheels has no traction and the
other does, this feature will allow the wheel with
traction to move the vehicle.
Windows
Manual Windows
Turn the hand crank on each door to raise or lower your
manual side door windows.
Power Windows (If Equipped)
If you have the optional power windows, the controls
are on each of the side doors. With power windows, the
switches control the windows when the ignition is on, in
ACCESSORY, or when Retained Accessory Power
(RAP) is present. (See ªRetained Accessory Powerº in
the Index.) The driver's door has a switch for the
passenger window as well.

2-38 Cruise Control (If Equipped)
With cruise control, you can
maintain a speed of about
25 mph (40 km/h) or more
without keeping your foot
on the accelerator. This can
really help on long trips.
Cruise control does not
work at speeds below about
25 mph (40 km/h).
If you have an automatic transmission and you apply
your brakes, the cruise control will shut off.
If you have a manual transmission and you apply your
brakes or push the clutch pedal, the cruise control will
shut off.CAUTION:

Cruise control can be dangerous where you
can't drive safely at a steady speed. So,
don't use your cruise control on winding
roads or in heavy traffic.

Cruise control can be dangerous on
slippery roads. On such roads, fast changes
in tire traction can cause needless wheel
spinning, and you could lose control. Don't
use cruise control on slippery roads.

4-9
Remember: Anti-lock doesn't change the time you need
to get your foot up to the brake pedal or always decrease
stopping distance. If you get too close to the vehicle in
front of you, you won't have time to apply your brakes
if that vehicle suddenly slows or stops. Always leave
enough room up ahead to stop, even though you have
anti
-lock brakes.
Using Anti
-Lock
Don't pump the brakes. Just hold the brake pedal down
firmly and let anti
-lock work for you. You may feel the
brakes vibrate, or you may notice some noise, but this is
normal. On vehicles with four
-wheel drive, your
anti
-lock brakes work at all times -- whether you
are in two
-wheel drive or four-wheel drive.
Braking in Emergencies
With anti-lock, you can steer and brake at the same
time. In many emergencies, steering can help you more
than even the very best braking.
Steering
Power Steering
If you lose power steering assist because the engine
stops or the system is not functioning, you can steer but
it will take much more effort.
Steering Tips
Driving on Curves
It's important to take curves at a reasonable speed.
A lot of the ªdriver lost controlº accidents mentioned on
the news happen on curves. Here's why:
Experienced driver or beginner, each of us is subject to
the same laws of physics when driving on curves. The
traction of the tires against the road surface makes it
possible for the vehicle to change its path when you turn
the front wheels. If there's no traction, inertia will keep
the vehicle going in the same direction. If you've ever
tried to steer a vehicle on wet ice, you'll understand this.
The traction you can get in a curve depends on the
condition of your tires and the road surface, the angle at
which the curve is banked, and your speed. While you're
in a curve, speed is the one factor you can control.
Suppose you're steering through a sharp curve. Then you
suddenly accelerate. Both control systems
-- steering and
acceleration
-- have to do their work where the tires meet
the road. Adding the sudden acceleration can demand too
much of those places. You can lose control.
What should you do if this ever happens? Ease up on the
accelerator pedal, steer the vehicle the way you want it
to go, and slow down.

4-13
Loss of Control
Let's review what driving experts say about what
happens when the three control systems (brakes, steering
and acceleration) don't have enough friction where the
tires meet the road to do what the driver has asked.
In any emergency, don't give up. Keep trying to steer and
constantly seek an escape route or area of less danger.
Skidding
In a skid, a driver can lose control of the vehicle.
Defensive drivers avoid most skids by taking reasonable
care suited to existing conditions, and by not ªoverdrivingº
those conditions. But skids are always possible.
The three types of skids correspond to your vehicle's
three control systems. In the braking skid, your wheels
aren't rolling. In the steering or cornering skid, too
much speed or steering in a curve causes tires to slip and
lose cornering force. And in the acceleration skid, too
much throttle causes the driving wheels to spin.
A cornering skid and an acceleration skid are best
handled by easing your foot off the accelerator pedal.If your vehicle starts to slide, ease your foot off the
accelerator pedal and quickly steer the way you want the
vehicle to go. If you start steering quickly enough, your
vehicle may straighten out. Always be ready for a
second skid if it occurs.
Of course, traction is reduced when water, snow, ice,
gravel or other material is on the road. For safety, you'll
want to slow down and adjust your driving to these
conditions. It is important to slow down on slippery
surfaces because stopping distance will be longer and
vehicle control more limited.
While driving on a surface with reduced traction, try
your best to avoid sudden steering, acceleration or
braking (including engine braking by shifting to a lower
gear). Any sudden changes could cause the tires to slide.
You may not realize the surface is slippery until your
vehicle is skidding. Learn to recognize warning
clues
-- such as enough water, ice or packed snow on
the road to make a ªmirrored surfaceº
-- and slow down
when you have any doubt.
Remember: Any anti
-lock brake system (ABS) helps
avoid only the braking skid.

4-17 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.
Surface 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.
Surface 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 ªDrunken Drivingº in the Index.

4-18 Driving on Off-Road Hills
Off-road driving often takes you up, down or across a
hill. Driving safely on hills requires good judgment and
an understanding of what your vehicle can and can't do.
There are some hills that simply can't be driven, no
matter how well built the vehicle.
CAUTION:
Many hills are simply too steep for any vehicle.
If you drive up them, you will stall. If you drive
down them, you can't control your speed. If you
drive across them, you will roll over. You could be
seriously injured or killed. If you have any doubt
about the steepness, don't drive the hill.
Approaching a Hill
When you approach a hill, you need to decide if it's one
of those hills that's just too steep to climb, descend or
cross. Steepness can be hard to judge. On a very small
hill, for example, there may be a smooth, constant
incline with only a small change in elevation where you
can easily see all the way to the top. On a large hill, the incline may get steeper as you near
the top, but you may not see this because the crest of the
hill is hidden by bushes, grass or shrubs.
Here are some other things to consider as you
approach a hill.

Is there a constant incline, or does the hill get sharply
steeper in places?

Is there good traction on the hillside, or will the
surface cause tire slipping?

Is there a straight path up or down the hill so you
won't have to make turning maneuvers?

Are there obstructions on the hill that can block your
path (boulders, trees, logs or ruts)?

What's beyond the hill? Is there a cliff, an
embankment, a drop
-off, a fence? Get out and walk the
hill if you don't know. It's the smart way to find out.

Is the hill simply too rough? Steep hills often have
ruts, gullies, troughs and exposed rocks because they
are more susceptible to the effects of erosion.

4-25
Hard packed snow and ice offer the worst tire traction. On
these surfaces, it's very easy to lose control. On wet ice, for
example, the traction is so poor that you will have difficulty
accelerating. And if you do get moving, poor steering and
difficult braking can cause you to slide out of control.
CAUTION:
Driving on frozen lakes, ponds or rivers can be
dangerous. Underwater springs, currents under
the ice, or sudden thaws can weaken the ice. Your
vehicle could fall through the ice and you and
your passengers could drown. Drive your vehicle
on safe surfaces only.
Driving in Water
Light rain causes no special off-road driving problems.
But heavy rain can mean flash flooding, and flood
waters demand extreme caution.
Find out how deep the water is before you drive through
it. If it's deep enough to cover your wheel hubs, axles or
exhaust pipe, don't try it
-- you probably won't get
through. Also, water that deep can damage your axle
and other vehicle parts.If the water isn't too deep, then drive through it slowly.
At fast speeds, water splashes on your ignition system and
your vehicle can stall. Stalling can also occur if you get
your tailpipe under water. And, as long as your tailpipe is
under water, you'll never be able to start your engine.
When you go through water, remember that when your
brakes get wet, it may take you longer to stop.
CAUTION:
Driving through rushing water can be dangerous.
Deep water can sweep your vehicle downstream
and you and your passengers could drown. If it's
only shallow water, it can still wash away the
ground from under your tires, and you could lose
traction and roll the vehicle over. Don't drive
through rushing water.
See ªDriving Through Waterº in the Index for more
information on driving through water.

6-49 Buying New Tires
To find out what kind and size of tires you need, look at
the Certification/Tire label.
The tires installed on your vehicle when it was new had
a Tire Performance Criteria Specification (TPC Spec)
number on each tire's sidewall. When you get new tires,
get ones with that same TPC Spec number. That way
your vehicle will continue to have tires that are designed
to give proper endurance, handling, speed rating,
traction, ride and other things during normal service on
your vehicle. If your tires have an all
-season tread
design, the TPC number will be followed by an ªMSº
(for mud and snow).
If you ever replace your tires with those not having a
TPC Spec number, make sure they are the same size,
load range, speed rating and construction type (bias,
bias
-belted or radial) as your original tires.
CAUTION:
Mixing tires could cause you to lose control while
driving. If you mix tires of different sizes or types
(radial and bias
-belted tires), the vehicle may not
handle properly, and you could have a crash.
Using tires of different sizes may also cause
damage to your vehicle. Be sure to use the same
size and type tires on all wheels.
It's all right to drive with your compact
spare (if you have one). It was developed for use
on your vehicle.
CAUTION:
If you use bias-ply tires on your vehicle, the
wheel rim flanges could develop cracks after
many miles of driving. A tire and/or wheel could
fail suddenly, causing a crash. Use only radial
-ply
tires with the wheels on your vehicle.