1995 GMC SIERRA traction control

A CAUTION:
Idling the engine with the air system control off could allow
dangerous exhaust into your vehicle (see the earlier Caution
under “Engine Exhaust”).
Also, idling in a closed-in place can let deadly carbon monoxide
~ (CO) into your vehicle even if the fan switch is at the highest
setting. One place this can happen is a garage. Exhaust
- with
CO - can come in easily. NEVER park in a garage with the
engine running.
Another closed-in place can be
a blizzard. (See “Blizzard” in the
Index.)
A 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).
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). Always
set your parking brake. Follow the proper steps to be sure your vehicle
won’t move. See “Shifting Into PARK
(P)“ in the Index.
If you’re pulling a trailer. see ”Towing a Trailer“ in the Index.
Four- Wheel Drive
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 it’s operation. Read the part
that follows before using four-wheel drive.
You should use 2-WHEEL
HIGH (2H) for most normal driving conditions.
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Remember: Anti-lock doesn’t change the time you need to get your foot up
to the brake pedal. 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.
To Use Anti-Lock
Don’t pump the brakes. Just hold the brake pedal down 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
Use your anti-lock braking system when you need to. 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 “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.
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Try not to pass more than one vehicle at a time on two-lane roads.
Reconsider before passing the next vehicle.
0 Don’t overtake a slowly moving vehicle too rapidly. Even though the
brake lights are
not flashing, it may be slowing down or starting to turn.
If you’re being passed, make it easy for the following driver to get
ahead
of you. Perhaps you can ease a little to the right.
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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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:
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 CAUTION:
When you’re driving off road, bouncing and quick changes in
direction can easily throw you out of position. This could cau\
se
you to lose control and crash.
So, whether you’re driving on or
off the road, you and your passengers should wear safety belts.
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.
Stttface 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.
Surjace 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.)
0 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.
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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.
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.
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 darnage 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.
A 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 inches deep, it can still wash
away the ground
from under your tires, and you could lose
l traction and roll the vehicle over. Don’t drive through rushing
water.
If you have a diesel engme, see “Driving Through Water (Diesel Engines)”
in the Index for more information on driving through water.
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less traction. It‘s always wise to go slower and be cautious if rain starts to
fall while you are driving. The surface may get wet suddenly when your
reflexes are tuned for driving on dry pavement.
The heavier the rain, the harder
it is to see. Even if your windshield wiper
blades are
in good shape, a heavy rain can make it harder to see road signs
and traffic signals, pavement markings, the edge of the road, and even
people walking.
It‘s wise to keep
your wiping equipment in good shape and keep your
windshield washer tank filled. Replace your windshield wiper inserts when
they show signs
of streaking or missing areas on the windshield, or when
strips
of rubber start to separate from the inserts.
Driving too fast through large water puddles or even going through
some
car washes can cause problems, too. The water may affect your brakes. Try
to avoid puddles. But
if you can’t, try to slow down before you hit them.
A CAUTION:
Wet brakes can cause accidents. They won’t work 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.
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A CAUTION:
If you operate your vehicle with a tire that is badly
underinflated, the tire can overheat. An overheated tire
can lose
air suddenly or catch fire. You or others could be injured. Be
sure all tires (including the spare, if any) are properly inflated.
Buying New Tires
To find out what kind and size of tires you need, look at the
CertificationRire label.
The tires installed on your vehicle when
it was new 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.
I A 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.
Be sure to use the same size and type tires on all four wheels.
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 treadwear, traction and temperature performance.
(This applies only to
vehicles sold in the United States.)
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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. 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.
These grades are molded on the sidewalls of passenger car tires.
While the tires available as standard or optional equipment on General
Motors vehicles may vary with respect to these grades, all such tires meet
General Motors performance standards and have been approved for use on
General Motors vehicles.
All passenger type (P Metric) tires must conform
to Federal safety requirements in addition to these grades.
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