all conditions-both on and off paved
surfaces, no matter
if the weather is fair
or foul.
The heart of the AWD system is the
transfer case. Here, engine power is
divided by an interaxle differential.
Under normal conditions,
it sends 65
percent of the torque to the rear axle and
the other 35 percent to the front axle.
But on a slippery surface, a viscous
clutch in the transfer case adjusts the
65/35 proportion according to need,
sending more power to the axle with
traction.
Another feature of the AWD system
that helps Bravada keep its grip is the
limited-slip rear axle. In conditions
where one rear wheel
loses traction but
the other still has some-as when one
wheel hits an icy patch or slips onto a
muddy road shoulder-this design
provides power to the wheel with
traction. And AWD is simple. It’s
always there-working.
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; and the condition of
your brakes. 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. Your brakes may not
have time to cool between hard stops.
Your 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 engine ever stops while you’re
driving, brake normally but don’t pump
your brakes. If you do, the pedal may
get harder to push down. If your 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 may take longer to stop and
the brake pedal will be harder to push.
109
ProCarManuals.com
Engine Fan Noise
This vehicle has a clutched engine
cooling fan. When the clutch is engaged,
the fan spins faster to provide more air
to cool the engine. In most everyday
driving conditions the clutch is not
engaged. This improves fuel economy
and reduces fan noise. Under heavy
vehicle loading, trailer towing and/or
high outside temperatures, the fan speed
increases when the clutch engages.
So
you may hear an increase in fan noise.
This is normal and should not be
mistaken as the transmission slipping or
making extra shifts. It is merely the
cooling system functioning properly.
The fan will slow down when additional
cooling is not required and the clutch
disengages. You may also hear this fan
noise when you start the engine. It will
go away
as the fan clutch disengages.
I Ifa Tire Goes Flat
It’s unusual for a tire to “blow out”
while you’re driving, especially if you
maintain your tires properly. If air goes
out of a tire, it’s much more likely to
leak out slowly. But if you should ever
have a “blowout,” here are a few tips
about what to expect and what to do:
If a front tire fails, the flat tire
will
create a drag that pulls the vehicle
toward that side. Take your foot
off the
accelerator pedal and grip the steering
wheel firmly. Steer to maintain lane
position, then gently brake to a stop
well out of the traffic lane.
A rear blowout, particularly on a curve,
acts much like a skid and may require
the same correction you’d use in a skid.
In any rear blowout, remove your foot
from the accelerator pedal. Get the
vehicle under control by steering the
way you want the vehicle to go. It may
be very bumpy and noisy, but you can
still steer. Gently brake to a stop, well
off the road if possible.
If a tire goes
flat, the next section shows
how to use your jacking equipment to
change a flat tire safely.
I Changing a Flat Tire
If a tire goes flat, avoid further tire and
wheel damage by driving slowly to a
level place. Turn
on your hazard
warning flashers.
151
ProCarManuals.com
