Cadillac 2009 XLR Automobile User Manual


 
Braking
See Brake System Warning Light on page 3-47.
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.
Avoid needless heavy braking. Some people drive
in spurts — heavy acceleration followed by heavy
braking rather than keeping pace with traffic. This is
a mistake. The brakes might not have time to cool
between hard stops. The brakes will wear out much
faster if you do a lot of heavy braking. If you keep pace
with the traffic and allow realistic following distances,
you will eliminate a lot of unnecessary braking.
That means better braking and longer brake life.
If your vehicle’s engine ever stops while you are driving,
brake normally but do not pump the brakes. If you do,
the pedal could get harder to push down. If the
engine stops, you will still have some power brake
assist. But you will use it when you brake. Once the
power assist is used up, it can take longer to stop and
the brake pedal will be harder to push.
Adding non-dealer/non-retailer accessories can affect
your vehicle’s performance. See Accessories and
Modifications on page 6-3.
5-4