BMW BMW AG X5 4.4i Automobile User Manual


 
122n
Disc brakes
Disc brakes furnish optimum decelera-
tion and braking control and greater
fade resistance under heavy use.
When the vehicle is driven only occa-
sionally, during extended periods when
the vehicle is not used at all, and in op-
erating conditions where brake applica-
tions are less frequent, there is an in-
creased tendency for corrosion of the
rotors and accumulation of contamina-
tion on the brake pads. This occurs be-
cause the minimal pressure which must
be exerted by the pads to clean the ro-
tors by brake applications is not
reached.
If the brake rotors are corroded, they
will tend to respond to braking with a
pulsating effect which even extended
application will fail to cure.
For your own safety: use only
brake pads that BMW has re-
leased for your particular vehicle
model. BMW cannot evaluate non-ap-
proved brake pads to determine if they
are suited for use, and therefore cannot
ensure the operating safety of the vehi-
cle if they are installed.<
Driving notes
When driving in wet conditions and in
heavy rain, it is advisable to apply light
pressure to the brake pedal every few
miles (kilometers). Watch traffic condi-
tions to ensure that this maneuver does
not endanger other road users. The
heat which is generated by the brake
applications helps to dry the brake
pads and rotors.
Maximum braking force is obtained
while the wheels continue to rotate,
peaking when the wheels remain on the
verge of locking without actually doing
so. ABS maintains this state automati-
cally. If the ABS fails, you should revert
to the staggered braking technique
(refer to page 124).
Extended or steep mountain descents
do not necessarily have to lead to re-
duced braking efficiency. Move the se-
lector lever to the appropriate lower
range in which only minimal periodic
brake applications are required.
You can increase the engine's braking
effect by selecting progressively lower
gears, downshifting as far as 1st gear,
on steep descents.
If engine braking should prove to be in-
adequate, you should still avoid ex-
tended, continuous braking. Instead of
maintaining low to moderate pressure
over an extended period of time, you
should decelerate by applying more
substantial pressure to the brake pedal
(watch for following traffic), then releas-
ing the pedal, then repeating the appli-
cation. This staggered braking tech-
nique allows the brakes to cool in the
intervals between active braking
phases, preventing overheating and en-
suring that full braking capacity remains
available at all times.
Do not coast with the selector le-
ver in “Neutral“. Do not drive with
the engine shut off. The engine pro-
vides no braking effect when the trans-
mission is in “Neutral“, and there is no
power-assist for braking or steering
when the engine is not running.
Have brake inspections performed at
an authorized BMW center only. If you
do not, parts of the four-wheel drive
system could be damaged.
Never allow floor mats, carpets or any
other objects to protrude into the area
around the accelerator and brake ped-
als and obstruct their movement.<
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