2004 BMW M3 CONVERTIBLE maintenance

115
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.
Extended or steep mountain descents
should be driven in the gear in which
only minimal periodic brake applica-
tions are required. By minimizing the
loads placed on the brake system, this
strategy helps ensure that optimal
brake system response will remain
available at all times. Stay within the
allowable rpm range. For additional
information, refer to page 79.Do not coast with the clutch
depressed or with the gearshift
lever in idle. Do not coast with the
engine switched off. If you do so the
engine provides no braking effect and
there is no power assist for braking or
steering when the engine is not run-
ning.<
Brake pads
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.<
Hardtop*It is not necessary to remove the fabric
top even in the winter, when the hard-
top is generally in constant use. But you
can also remove it easily at any time.
Before the fabric top is stored in the
convertible top compartment, it must
be absolutely dry in order to avoid
water spots and mildew from forming.
The hardtop offers reading lamps and
clothes hooks that can be used just by
pressing. It is also possible to mount a
luggage rack on the roof. Please con-
sult your BMW center.
When hanging clothing from the
hooks, be sure that they will not
obstruct the driver's vision. Do not hang
heavy objects on the hooks. If you do
so, they could cause personal injury
during braking or evasive maneuvers.<
Two people are required for installation
or removal. Work with extreme caution
in order to avoid paint damage and
damage to the body or hardtop.
To facilitate hardtop installation or
removal, you can obtain a specially
designed hardtop lift* or hardtop rack*
at your BMW center.
Brake system
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117
5. Before installing, first flip the cover
panels that are located underneath
the left and right interior lamps
down. To do this, press on the
slight bump on the cover panel.
There is a holder in the cover panel
to securely store the trim pieces
that have been removed – see
arrow 1
6. Open the red release levers as far
as the stop will allow – see arrow 2
7. Position the hardtop onto the sup-
ports with the help of a second
person. Be sure to put the mount-
ings exactly into the proper brack-
ets
Lift the hardtop carefully. Be
extremely careful not to shift the
seals. Seals that have been shifted out
of place or actually pulled out cause
leaks.<
8. In the back, close the red locking
levers by turning to the inside as far
as the stop located behind the trim
will allow. Flip the cover panels
back into place
9. To lock the hardtop in the front,
keep pressing on the front locking
levers until you hear them engage
10. Check the rubber weather-strip-
ping between the windshield frame
and the hardtop on both the left
and right sides. If it is folded or
bent out of place, you should
smooth it back into position by
hand to ensure secure and reliable
sealing.RemovalFollow the same procedure as when
installing, just reverse the steps.
Hardtop*
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118Wheels and tires
Tire inflation pressureInformation for your safetyThe factory-approved tires are matched
to your vehicle and have been selected
to provide optimum safety and driving
comfort when used properly.
It is not merely the tire's service life, but
also driving comfort and – above all else
– driving safety that depend on the con-
dition of the tires and the maintenance
of the specified tire pressure.
Incorrect tire inflation pressure is
a frequent cause of tire damage. It
also significantly influences the road-
holding ability of your BMW. Check tire
inflation pressures on a regular basis,
refer to page 25, at least every two
weeks and before beginning a longer
trip. If this is not done, incorrect tire
pressures can cause driving instability
and tire damage, ultimately resulting in
accidents.<
Tire conditionTire tread – tire damageInspect your tires frequently for tread
wear, signs of damage and for foreign
objects lodged in the tread. Check the
tread depth.
Tread depth should not be allowed to
go below 1/8 in / 3 mm, even though
the legally specified minimum tread
depth is only 1/16 in / 1.6 mm.
Below 1/8 in / 3 mm tread depth, there
is a great risk of hydroplaning, even at
relatively moderate speeds and with
only small amounts of water on the
road. Tread wear indicators in the
tread-groove base – see arrow – are
distributed around the wheel circumfer-
ence and are labeled on the tire side-
wall with TWI – Tread Wear Indicator. At
a tread depth of 1/16 in / 1.6 mm, the
indicators signal that the legally permis-
sible wear limit has been reached.

119
Do not drive on a deflated – flat –
tire. A flat tire greatly impairs
steering and braking response, and can
lead to complete loss of control over
the vehicle.
Avoid overloading the vehicle so that
the permitted load on the tires is not
exceeded. Overloading can lead to
overheating and internal tire damage.
This can result in a sudden loss of tire
inflation pressure.
Unusual vibrations encountered during
normal vehicle operation can indicate
tire failure or some other vehicle defect.
This type of problem can be caused by
contact with curbs, etc. This is also true
for irregularities in the vehicle's han-
dling characteristics, such as a pro-
nounced tendency to pull to the left or
right. Should this occur, respond by
immediately reducing your speed. Pro-
ceed carefully to the nearest BMW cen-
ter or professional tire center, or have
the vehicle towed in to have it, its
wheels or its tires inspected.
Tire damage, up to and including blow-
outs, can endanger the lives of both the
vehicle occupants and other road
users.<
Tire replacementTo maintain good handling characteris-
tics, only use a full set of tires of the
same brand and tread configuration.
Comply with the specified tire inflation
pressures, and be sure to have the
wheel and tire assembly balanced
every time you change a tire or wheel.DOT quality grades>Treadwear
>Traction AA A B C
>Temperature A B C
All passenger car tires must con-
form to Federal Safety Require-
ments in addition to these grades. rating based on the wear rate of the tire
when tested under controlled condi-
tions on a specified government test
course.
For example, a tire graded 150 would
wear one and one-half – 1
1/2 – times as
well on the government course as a tire
graded 100. The relative performance
of tires depends upon the actual condi-
tions of their use, however, and may
depart significantly from the norm due
to variations in driving habits, service
practices and differences in road char-
acteristics and climate.TractionThe traction grades, from highest to
lowest, are AA, A, B and C.
Those grades represent the tire's ability
to stop on wet pavement as measured
under controlled conditions on speci-
fied government test surfaces of
asphalt and concrete. A tire marked C
may have poor traction performance.
The traction grade assigned to
this tire is based on straight-
ahead braking traction tests, and does
not include acceleration, cornering,
hydroplaning, or peak traction charac-
teristics. highest – B and C, representing the
tire's resistance to the generation of
heat and its ability to dissipate heat
when tested under controlled condi-
tions on a specified indoor laboratory
test wheel.
Tire condition
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121
Wheel and tire combinationsThe right choice
BMW recommends using only
wheels and tires that have been
approved by BMW for your particular
vehicle model, as otherwise body con-
tact and serious accidents can result
despite the use of the same nominal
size, e.g. due to manufacturing toler-
ances. If non-approved wheels and
tires are used, BMW cannot evaluate
their suitability, and therefore cannot be
held liable for driving safety.<
BMW tests certain tire brands for each
tire size, classifies them as road-safe
and approves them. Consult your BMW
center for more information. Observe
any country-specific regulations, e.g.
on making a corresponding entry in the
vehicle documents.
The correct wheel and tire combi-
nation affects different systems
such as ABS, DSC, Flat Tire Monitor.
The function of these systems is
impaired if improper wheel and tire
combinations are used.
Therefore, only use tires of the same
brand and same tread configuration on
the vehicle and, for example following a
tire failure, restore the approved wheel
and tire combination as soon as possi-
ble.<
The use of rims and lug bolts that
do not meet the specifications of
the original factory-installed equipment
will affect the safe operation of your
vehicle and may cause an accident and
personal injury.
Never mix tires of different design, such
as steel-belted radials with radial bias-
belted or bias-ply tires, etc. Mixing tire
types will adversely affect roadholding
and can lead to loss of vehicle con-
trol.<
StorageAlways store tires in a cool, dry place.
Store them away from light whenever
possible. Protect the tires against con-
tact with oil, grease and fuel.
Do not exceed the maximum tire infla-
tion pressures specified on the tire
sidewall.
OverviewControlsMaintenanceRepairsDataIndex

123 In the engine compartment
HoodTo releasePull the lever located under the left-
hand side of the instrument panel.
Do not attempt to service your
vehicle if you do not have the
required technical background. Failure
to work in an informed, professional
manner when servicing components
and materials constitutes a safety haz-
ard for vehicle occupants and other
road users. If you are not familiar with
the guidelines, BMW recommends that
you have the operations performed by
your BMW center.<
To openPull the release handle and open the
hood.
It is not possible to drive off using
SMG Drivelogic when the hood is
open.<
To closePull the hood downwards and allow the
hood to fall from a minimum height of
1 ft/30 cm so that it audibly engages.
Check for proper locking by pulling on
the hood at the left and right above the
headlamps.
To avoid injuries, be sure that the
travel path of the hood is clear
when it is closed, following the same
safety precautions used in all closing
procedures.
If you notice while driving that the hood
is not completely closed, stop immedi-
ately and close it securely.<
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125
1Filler neck for windshield and head-
lamp washer cleaning system126
2Coolant expansion tank128
3Auxiliary terminal for jump-starting –
positive terminal147
4Engine oil filler neck127
5Expansion tank for SMG Drivelogic
hydraulic unit – checking and possi-
ble refilling by your BMW center70
6Engine oil dipstick126
7Filler neck for brake fluid129Engine compartment essentials
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127
Adding engine oilOnly add engine oil when the oil level
has dropped to just above the lower
mark on the dipstick.
Do not fill beyond the upper mark on
the dipstick. Excess oil will damage the
engine.
Before checking the engine oil level
after topping up, restart the engine and
allow it to run to obtain a correct dis-
play. Then proceed as described under
Checking the oil level.
BMW engines are designed to
operate without oil additives; the
use of additives could lead to damage
in some cases. This also applies to the
manual transmission, the differential,
and the power steering system.<
Recommendation: have the oil changed
by your BMW center.
Continuous exposure to used oil
has caused cancer in laboratory
testing. For this reason, thoroughly
wash any areas of skin that come into
contact with oil using soap and water.
Store oils, grease and similar materials
so that they are inaccessible to chil-
dren. Comply with warning labels and
information on containers.<
Comply with the applicable envi-
ronmental laws regulating the dis-
posal of used oil. extremely important for the function
and life of an engine. Based on exten-
sive testing, BMW has approved only
certain grades of engine oil.
Use only oils approved for your vehicle
model.
Ask your BMW center for details
concerning oils that have been
approved. You can also call BMW of
North America toll-free at 1-800-831-
1117 or visit this website:
www.bmwusa.com to obtain this infor-
mation.<
Alternative oil typesIf a High Performance Synthetic Oil
approved by BMW should be unavail-
able, you may use small volumes of
other synthetic oils for topping up
between oil changes. The following
data must appear on the packaging:
>Viscosity
preferred: SAE 10W-60
alternative: SAE 5W-40 or
SAE 10W-40
>Specifications
preferred: API SJ/CF
alternative: API SJ – also SK, SL, S
etc.Low ambient temperaturesThe oils used by BMW at the factory for
your vehicle model can be used at virtu-
ally any ambient temperature.
Engine oil
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