1998 GMC SIERRA traction control

Washer fluid will spray as long as you push the paddle.
When you let
go of the paddle, the wipers will continue
to wipe for
a few seconds and then e.ither stop or return
to the preset speed.
The use of a hood-mounted air deflector may adversely
affect windshield wiper and washer performance.
Cruise Control (If Equipped)
really help on long trips.
Cruise control does not
work at speeds below about
, .. .. .. . , . :.!r+.l .. 25 mph (40 km/h).
When
you apply your brakes, the cruise control
shuts
off.
C * ‘JTIOT ;
0 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.
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.
Cruise control can be dangerous on
Setting Cruise Control
If you leave your cruise control switch on W,AI
you’re not using cruise, you might hit a button
and
go into cruise when you don’t want to. You
could
be startled and even lose control. Keep the
cruise control switch off until
you want to use it.
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Speed Sensitive Steering
This system varies the amount of steering effort
proportionate
to your vehicle speed. Steering is easier at
lower speeds for maneuvering and parking ease.
As your
vehicle speed increases,
the steering effort also
increases.
At highway speeds, the amount of steering
effort is increased for vehicle control and stability.
Steering Tips
Driving on Curves
It’s important to take curves at a reasonable speed.
A lot of the “driver lost control” 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.
Speed
limit signs near curves warn that you should
adjust your speed.
Of course, the posted speeds are
based on good weather and road conditions. Under less
favorable conditions you’ll want to go slower.
If you need to reduce your speed as you approach a
curve, do
it before you enter the curve, while your front
wheels are straight ahead.
Try to adjust your speed
so you can “drive” through the
curve. Maintain a reasonable, steady speed. Wait to
accelerate
until you are out of the curve, and then
accelerate gently into the straightaway.
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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 “overdriving” 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 “mirrored surface” -- and slow down when you
have any doubt.
Remember:
Any anti-lock brake system (ABS) helps
avoid only the braking skid.
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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 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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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.
I a CAUTION:
Many hills are simply too steep for any vehicle. If
you drive up them, you will stall. If you drive
1 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 tojudge. 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.
0
0
0
0
0
0
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.
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I-
I A CAUTION:
-
~ Getting out on the downhill (low) side of a vehicle
~ stopped across an incline is dangerous. If the
vehicle
rolls over, you could be crushed or killed.
Always get out on the uphill (high) side of the
~ vehicle and stay well clear of the rollover path.
Driving in Mud, Sand, Snow or Ice
When you drive in mud, snow or sand, your wheels
won’t get good traction. You can’t accelerate
as
quickly, turning is more difficult, and you’ll need
longer braking distances.
It‘s best to use a low gear when you’re
in mud -- the
deeper the mud, the lower the gear.
In really deep mud,
the idea
is to keep your vehicle moving so you don’t
get stuck.
When you drive on sand, you’ll sense
a change in wheel
traction. But
it will depend upon how loosely packed the
sand is. On loosely packed sand (as on beaches or sand
dunes) your tires will tend to sink into the sand. This has
an
effect on steering, accelerating and braking. You may
want to reduce the air pressure in your tires slightly
when driving on sand. This will improve traction.
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.
r A 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.
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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 “MS”
(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.
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.
I A CAUTION:
If you use biasuply 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.
Uniform Tire Quality Grading
The following information relates to the system
developed by the United States National Highway
Traffic Safety Administration, which grades tires by
I treadwear, traction and temperature performance. (This
applies only to vehicles sold
in the United States.) The
grades are molded on the sidewalls of most passenger
car tires. The Uniform Tire Quality Grading system does
not apply to deep tread, winter-type snow tires,
space-saver or temporary use spare tires, tires
with
nominal rim diameters of 10 to I2 inches (25 to 30 cm),
or to some limited-production tires.
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While the tires available on General Motors passenger
cars and light trucks may vary with respect to these
grades, they must also conform to Federal safety
requirements and additional General Motors Tire
Performance Criteria (TPC) standards.
Treadwear
The treadwear grade is a comparative rating based on
the wear rate of the tire when tested under controlled
conditions on a specified government test course. For
example, a tire graded 150 would wear one and a half
(1 1/2) times as well on the government course as a tire
graded
100. The relative performance of tires depends
upon the actual conditions of their use, however, and
may depart significantly from the norm due to variations
in driving habits, service practices and differences in
road characteristics and climate.
Traction -- A, B, C
The traction grades, from highest to lowest, are A, B, and
C, and they represent the tire’s ability to stop
on wet
pavement
as measured under controlled conditions on
specified government test surfaces of asphalt and concrete.
A tire marked C may have poor traction performance. Warning:
The traction grade assigned to this tire is based
on braking (straight ahead) traction tests and does not
include cornering (turning) traction.
Temperature -- A, B, C
The temperature grades are A (the highest), B, and C,
representing the tire’s resistance to the generation of
heat and its ability
to dissipate heat when tested under
controlled conditions
on a specified indoor laboratory
test wheel. Sustained high temperature can cause the
material of
the tire to degenerate and reduce tire life, and
excessive temperature can lead to sudden tire failure.
The grade
C corresponds to a level of performance
which
all passenger car tires must meet under the
Federal Motor Vehicle Safety Standard
No. 109.
Grades B and A represent higher levels of performance
on the laboratory test wheel than the minimum required
by law.
Warning: The temperature grade for this tire is
established for a tire that is properly inflated and
not
overloaded. Excessive speed, underinflation, or
excessive loading, either separately or in combination,
can cause heat buildup and possible tire failure.
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