1997 OLDSMOBILE BRAVADA tires

Control of a Vehicle
You have three systems that make your vehicle go where
you want it to
go. They are the brakes, the steering and
the accelerator. All three systems have to do their work
at the places where the tires meet the road.
Braking
Braking action involves perception time and
reaction time.
First, you have to decide to push on the brake pedal.
That’s perception time. Then you have to bring up your
foot and do it. That’s reaction time.
Average reaction time is about 3/4 of a second. But
that’s only an average. It might be less with one driver
and as long as two or three seconds or more with
another. Age, physical condition, alertness, coordination
and eyesight all play a part.
So do alcohol, drugs and
frustration. But even in 3/4 of a second, a vehicle
moving at
60 mph (100 km/h) travels 66 feet (20 m).
That could be a lot of distance in an emergency, so
keeping enough space between your vehicle and others
is important.
And, of course, actual stopping distances vary greatly
with the surface of the road (whether it’s pavement or
gravel); the condition of the road (wet, dry, icy); tire
tread; the condition
of your brakes; the weight of the
vehicle and the amount of brake force applied.
~ Sometimes, as when you’re driving on snow or ice, it’s
1 easy to ask more of those control systems than the tires
and road can provide. That means you can lose control
of your vehicle.
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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
and let anti-lock work for you.
You may feel the brakes
vibrate, or you may notice some noise, but this is normal.
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 “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.
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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 system
-- 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 yo~~r 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.
Steering in Emergencies
There are times when steering can be more effective than
braking. For example, you come over a hill and find a
truck stopped
in your lane, or a car suddenly pulls out
from nowhere, or a child darts out from between parked
cars and stops right in front of you. You can avoid these
problems by braking
-- if you can stop in time. But
sometimes you can’t; there isn’t room. That’s the time \
for
evasive action
-- steering around the problem.
Your Oldsmobile can perform very well
in emergencies
like these. First apply your brakes. (See “Braking
in
Emergencies‘’ earlier in this section.) It is better to
remove
as much speed as you can from a possible
collision. Then steer around the problem, to the left or
right depending on the space available.
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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
Oldsmobile’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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Before You Go Off-Roading
There are some things to do before you go out. For
example, be sure to have all necessary maintenance and
service work done. Check to make sure all underbody
shields (if
so equipped) are properly attached. Be sure
you read all the information about your
four-wheel-drive vehicle in this manual.
Is there enough
fuel?
Is the spare tire fully inflated? Are the fluid levels
up where they should be? What are the local laws that
apply to off-roading where you’ll be driving? If you
don’t know, you should check with law enforcement
people in the area. Will you be on someone’s private
land? If
so, be sure to get the necessary permission.
Loading Your Vehicle for Off-Road Driving
There are some important things to remember about
how to load your vehicle.
0 The heaviest things should be on the load floor and
forward of your rear axle. Put heavier items as far
forward as you can.
0 Be sure the load is secured properly, so driving on
the off-road terrain doesn’t toss things around.
0 Cargo on the load floor piled higher than
the seatbacks can be thrown forward
during
a sudden stop. You or your
passengers could be injured. Keep cargo
below the top of the seatbacks.
0 Unsecured cargo on the load floor can be
tossed about when driving over rough
terrain. You or your passengers can be
struck by flying objects. Secure the
cargo properly.
0 Heavy loads on the roof raise the vehicle’s
center of gravity, making
it more likely to
roll over. You can be seriously or fatally
injured if the vehicle rolls over. Put heavy
loads inside the cargo area, not on the roof.
Keep cargo in the cargo area
as far forward
and low
as possible.
You’ll find other important information in this manual.
See “Vehicle Loading,” “Luggage Carrier” and “Tires’’
in the Index.
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Driving Across an Incline
Sooner or later, an off-road trail will probably go across
the incline
of a hill. If this happens, you have to decide
whether to try to drive across the incline. Here are some
things to consider:
A hill that can be driven straight up or down may be
too steep to drive across. When you go straight up or
down
a hill, the length of the wheel base (the
distance from
the front wheels to the rear wheels)
reduces the likelihood the vehicle will tumble end
over end.
But when you drive across an incline, the
much more narrow track width (the distance between
the left and right wheels) may not prevent the vehicle
from tilting and rolling over. Also, driving across an
incline puts more weight on the downhill wheels.
This could cause
a downhill slide or a rollover.
Surface conditions can be a problem when you drive
across
a hill. Loose gravel, muddy spots, or even wet
grass can cause your tires to
slip sideways, downhill.
If the vehicle slips sideways, it can hit something
that will trip it
(a rock, a rut, etc.) and roll over.
Hidden obstacles can make the steepness of the
incline even worse. If you drive across a rock with
the uphill wheels, or if the downhill wheels drop into
a rut or depression, your vehicle can
tilt even more.
For reasons like these, you need to decide carefully
whether to
try to drive across an incline. Just because
the trail goes across the incline doesn’t mean you
have
to drive it. The last vehicle to try it might have
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Driving across an incline that’s too steep will
make your vehicle roll over. You could be
seriously injured or killed.
If you have any doubt
about the steepness
of the incline, don’t drive
across it. Find another route instead.
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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.
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.
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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 stzt your engine.
When you go through water. remember that when your
brakes get wet,
it may take you longer to stop.
I
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 “Driving Through Water‘. in the Index for more
information
on driving through water.
After Off-Road Driving
Remove any brush or debris that has collected on the
underbody, chassis or under the hood. These
accumulations can be a fire hazard.
After operation
in mud or sand, have the brake linings
cleaned and checked. These substances can cause
steering, suspension, wheels, tires and exhaust system
for damage. Also, check the fuel lines and cooling
system for any leakage.
2 (.lazing and uneven braking. Check the body structure,
Your vehicle will require more frequent service due to
off-road use. Refer to the Maintenance Schedule for
additional information.
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