brake rotor BMW 325I WAGON 2003 Owners Manual

114Special operating instructions
Break-in proceduresTo ensure that your vehicle provides
maximum economy throughout a long
service life, we request that you
observe the following information.Engine and differentialUp to 1,250 miles/2,000 km:
Constantly vary both engine and vehicle
speeds, remembering not to exceed
4,500 rpm or 100 mph / 160 km/h dur-
ing this period.
Always obey all official speed limits.
Do not use full throttle, and avoid
pressing the accelerator beyond the
kickdown point during these initial
miles.
You can then proceed to increase both
engine and vehicle speeds once the ini-
tial 1,250 miles/2,000 km have elapsed.
You should also observe the same
break-in procedures if the engine or dif-
ferential should have to be replaced
later in the course of the vehicle's life.
TiresDue to technical factors associated
with their manufacture, tires do not
achieve their full traction potential until
after an initial break-in period. We thus
ask you to drive with extra care during
the first 200 miles/300 km.
Always obey all official speed limits.
When the vehicle is operated on
wet or slushy roads, a wedge of
water may form between the tire and
the road surface. This phenomenon is
referred to as hydroplaning and can
lead to partial or complete loss of trac-
tion, vehicle control and braking effec-
tiveness. Reduce your speed on wet
roads. before the brake pads and rotors
achieve the optimal pad-surface and
wear patterns required for trouble-free
operation and an extended service life
later on.
To break in the separate parking brake
drums, apply the parking brake lightly
when coasting to a standstill – at a traf-
fic signal, for instance – provided that
traffic conditions allow you to do so.
To avoid corrosion, repeat this proce-
dure from time to time.
The brake lamps do not come on
when the parking brake is set.
Vacuum for the brake system servo unit
on your BMW is available only when the
engine is running. When you move the
vehicle with the engine switched off –
when towing, for example – substan-
tially higher levels of pedal force will be
required to brake the vehicle. before the clutch starts to operate at
optimum efficiency. Remember to
engage the clutch carefully during this
initial period.
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116
Brake systemBrake fluid levelIf the brake fluid level is too low and
brake pedal travel has become longer,
there may be a defect in one of the two
brake system's hydraulic circuits.
Proceed to the nearest BMW cen-
ter. It may be necessary to apply
higher levels of pressure to the pedal
when stopping and braking distances
may also be longer. Please remember
to adapt your driving style accord-
ingly. with the vehicle parked or in storage,
and operating conditions in which brak-
ing is restricted to gentle, low-pressure
applications will all increase the ten-
dency for corrosion to form on the
rotors; this is often accompanied by a
simultaneous accumulation of contami-
nation on the brake pads. The pads
must exert a certain minimal level of
pressure against the rotors for the disc
brakes' inherent self-cleaning effect to
remain effective; the pressure available
under the above conditions may not
provide adequate cleansing.
If the brake rotors are corroded, they
will tend to respond to braking with a
pulsating effect that even extended
brake applications will fail to cure.
When driving in heavy rain and on wet
roads it is useful to apply light pressure
to the brake pedal every few miles.
Monitor traffic conditions to ensure that
this maneuver does not pose a hazard
to you or to other road users. The heat
generated in this process helps dry the
pads and rotors to ensure that your
brake system will respond with undi-
minished efficiency when you need it.
When descending steep hills and
extended grades, downshift to a gear
that will allow you to continue safely
with only a minimal amount of braking.
By minimizing the loads placed on the
brake system, this strategy helps
ensure that optimal brake system
response will remain available at all
times. Use care to avoid exceeding the
approved engine-speed range, refer to
page 71.
Do not coast with the clutch
depressed or with the transmis-
sion or selector lever in Neutral. Do not
coast with the engine shut off. The
engine provides no braking effect when
the clutch is depressed and there is no
power-assist for braking or steering
when the engine is not running.
BMW 325xi: always refer all brake
inspection and service work to your
BMW center, as failure to observe the
special procedures could result in dam-
age to components of the all-wheel
drive.
Never allow floor mats, carpets or any
other objects to protrude into the area
around the accelerator, clutch and
brake pedals and obstruct their move-
ment. For your own safety: use only
brake pads that BMW has
released for your particular vehicle
model. BMW cannot evaluate non-
approved brake pads to determine if
they are suitable for use, and therefore
cannot ensure the operating safety of
the vehicle if they are installed.<
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