2007 CADILLAC DTS PROFESSIONAL tires

Control of a Vehicle
The following three systems help to control your
vehicle while driving — brakes, steering, and
accelerator. At times, as when driving on snow or
ice, it is easy to ask more of those control
systems than the tires and road can provide.
Meaning, you can lose control of your vehicle. See
Traction Control System (TCS) on page 309.
Adding non-dealer/non-retailer accessories can
affect your vehicle’s performance. SeeAccessories
and Modications on page 353.
Braking
SeeBrake System Warning Light on page 229.
Braking action involves perception time and
reaction time.First, you have to decide to push on the brake
pedal. That is perception time. Then you have to
bring up your foot and do it. That is reaction time.
Average reaction time is about three-fourths of a
second. But that is 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 three-fourths 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 is
pavement or gravel; the condition of the road,
whether it is wet, dry, or icy; tire tread; the
condition of the brakes; the weight of the vehicle;
and the amount of brake force applied.
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Panic Brake Assist
Your vehicle may have a panic brake assist
system that monitors the intention of the driver
while braking. If the system senses that the driver
has applied hard/fast pressure to the brake
pedal, the system will generate additional
pressure, making it easier for the driver to maintain
brake application. When this happens the brake
pedal will feel easier to push. Just hold the
brake pedal down rmly and let the system work
for you. You may feel the brakes vibrate, or
you may notice some noise but this is normal. The
brakes will return to normal operation after the
brake pedal has been released.
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.
Magnetic Speed Variable Assist
Steering System
This system continuously adjusts the effort you
feel when steering at all vehicle speeds. It provides
ease when parking, yet a rm, solid feel at
highway speeds.
Steering Tips
It is important to take curves at a reasonable speed.
A lot of the “driver lost control” accidents mentioned
on the news happen on curves. Here is 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 is
no traction, inertia will keep the vehicle going in the
same direction. If you have ever tried to steer a
vehicle on wet ice, you will understand this.
The traction you can get in a curve depends on
the condition of the tires and the road surface, the
angle at which the curve is banked, and your
speed. While you are in a curve, speed is the
one factor you can control.
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Suppose you are 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.
SeeTraction Control System (TCS) on page 309.
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.
If you have StabiliTrak
®, the system may be
active. SeeStabiliTrak®System on page 311.
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 will want to
go slower.If you need to reduce your speed as you approach
a curve, do it before you enter the curve, while
the 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.
Adding non-dealer/non-retailer accessories can
affect your vehicle’s performance. SeeAccessories
and Modications on page 353.
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Remember that an outside convex mirror
makes the vehicle you just passed seem farther
away from you than it really is.
Try not to pass more than one vehicle at a time
on two-lane roads. Reconsider before passing
the next vehicle.
Do not overtake a slowly moving vehicle too
rapidly. Even though the brake lamps are not
ashing, it might be slowing down or starting
to turn.
If you are 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 us review what driving experts say about what
happens when the three control systems — brakes,
steering, and acceleration — do not have enough
friction where the tires meet the road to do what the
driver has asked.
In any emergency, do not 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,
the wheels are not 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 is best handled by easing your
foot off the accelerator pedal.
Remember: Any traction control system helps
avoid only the acceleration skid. If your traction
control system is off, then an acceleration
skid is also 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.
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If you have StabiliTrak®, the system may be
active. SeeStabiliTrak®System on page 311.
Of course, traction is reduced when water, snow,
ice, gravel, or other material is on the road.
For safety, you will 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 reducing vehicle speed 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.Driving at Night
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.
Here are some tips on night driving.
Drive defensively.
Do not drink and drive.
Adjust the inside rearview mirror to reduce the
glare from headlamps behind you.
Since you cannot see as well, slow down and
keep more space between you and other
vehicles.
Slow down, especially on higher speed roads.
Your vehicle’s headlamps can light up only so
much road ahead.
In remote areas, watch for animals.
If you are tired, pull off the road in a safe
place and rest.
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Driving in Rain and on Wet Roads
Rain and wet roads can mean driving trouble. On a
wet road, you cannot stop, accelerate, or turn as
well because your tire-to-road traction is not as
good as on dry roads. And, if your tires do not have
much tread left, you will get even less traction. It is
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 reexes 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 is wise to keep your windshield wiping equipment
in good shape and keep your windshield washer
uid reservoir lled with washer uid. 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.
{CAUTION:
Wet brakes can cause accidents. They
may not 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 the brake pedal
lightly until the brakes work normally.
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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 cannot, try
to slow down before you hit them.
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 are going fast enough. When your
vehicle is hydroplaning, it has little or no contact
with the road.
Hydroplaning does not 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 reections 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 is not a hard and fast rule about
hydroplaning. The best advice is to slow down
when it is raining.
Driving Through Deep Standing Water
Notice:If you drive too quickly through
deep puddles or standing water, water can
come in through the engine’s air intake
and badly damage the engine. Never drive
through water that is slightly lower than the
underbody of your vehicle. If you cannot avoid
deep puddles or standing water, drive
through them very slowly.
Driving Through Flowing Water
{CAUTION:
Flowing or rushing water creates strong
forces. If you try to drive through owing
water, as you might at a low water
crossing, your vehicle can be carried away.
As little as six inches of owing water can
carry away a smaller vehicle. If this
happens, you and other vehicle occupants
could drown. Do not ignore police warning
signs, and otherwise be very cautious
about trying to drive through owing water.
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Some Other Rainy Weather Tips
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.
Have good tires with proper tread depth. See
Tires on page 402.
City Driving
One of the biggest problems with city streets is
the amount of traffic on them. You will want
to watch out for what the other drivers are doing
and pay attention to traffic signals.
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