2003 BMW 330Ci CONVERTIBLE wheel

127 Wheels 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 inflation pressure.
Incorrect tire inflation pressure is
a frequent cause of tire damage.
Tire pressure also has a major effect on
your BMW's handling response. Be
sure to check the tire inflation pressure,
including the space-saver spare tire or
the spare tire, on a regular basis, at
least twice a month and before every
extended journey, refer to page 25.
Otherwise, incorrect tire pressure can
lead to poor handling, to tire damage
and 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 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.
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 vehi-
cle so that the permitted load on the
tires is not exceeded. Overloading can
lead to overheating and internal tire
damage.
The ultimate result can assume the
form of a sudden air loss.
Unusual vibrations encountered during
normal vehicle operation can indicate a
flat tire or some other vehicle malfunc-
tion. This type of problem can be
caused by contact with curbs, etc. This
is also true for irregularities in the vehi-
cle's handling characteristics, such as a
pronounced tendency to pull to the left
or right. Should this occur, respond by
immediately reducing your speed. Pro-
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128
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 sud-
den and complete air loss can endan-
ger the lives of both the vehicle occu-
pants and other road users.<
Tire replacementTo maintain good handling and vehicle
response, use only tires of a single
tread configuration from a single manu-
facturer.DOT quality gradesTread wear
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.
Sustained high temperature can cause
the material of the tire to degenerate
and reduce tire life, and excessive tem-
perature can lead to sudden tire failure.
The grade C corresponds to a level of
performance which all passenger car
Tire condition
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129
tires must meet under the Federal
Motor Vehicle Safety Standard No. 109.
Grades B and A represent higher levels
of performance on the laboratory test
wheel than the minimum required by
law.
The temperature grade for this tire
is established for a tire that is
properly inflated and not overloaded.
Excessive speed, underinflation, or
excessive loading, either separately or
in combination, can cause heat buildup
and possible tire failure. applicable on the tire sidewall between
tread shoulder and maximum section
width. For example:
Tread wear 200
Traction AA
Temperature A
BMW advises against using
retreaded tires, since driving
safety may be impaired. This is due to
the possible variations in casing struc-
tures and, in some cases, to their
extreme age, which can lead to a
decrease in their durability.<
Tire ageThe date on which the tire was manu-
factured is indicated by the code on the
sidewall:
DOT... 3502 indicates that the tire was
manufactured in week 35 of the year
2002.
BMW recommends the replacement of
all tires – including the spare tire* –
when the tires are no more than 6 years
old, even if a tire life of 10 years is pos-
sible.Run Flat tires*Run Flat tires consist of self-supporting
tires and special rims. The tire rein-
forcement ensures that the tire retains
some residual safety in the event of
pressure drop and driving remains pos-
sible to a restricted degree. The vehicle
is equipped with a Tire Pressure Moni-
tor (TPM) or Flat Tire Monitor, which
indicate a flat tire.
For additional information on Tire Pres-
sure Monitor (TPM) or Flat Tire Monitor
refer to pages 92, 93.
Run Flat tires are only possible in
conjunction with the Tire Pres-
sure Monitor (TPM) or Flat Tire Moni-
tor.<
Tire replacement
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130
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. BMW cannot evaluate all tires
and wheels on the market, and is thus
unable to guarantee that the vehicle will
continue to perform safely if unap-
proved tires and/or wheels are
mounted.<
For each tire size, BMW has assessed
the safe performance of specific tire
brands and approved them for use.
Consult any BMW center for details.
Comply with any local/national regula-
tions, for example by recording the tire
type in the vehicle documents.
The correct wheel and tire combi-
nation affects various systems
that would otherwise be impaired, for
example ABS, ASC+T/DSC and
ADB/DBC.
For this reason, use only tires of the
same manufacture and tread configura-
tion. In the event of a flat tire, for exam-
ple, remount the approved wheel and
tire combination as soon as possible.<
StorageStore tires in a cool, dry place, protect-
ing them against light whenever possi-
ble. Protect the tires against contact
with oil, grease and fuel.
Winter tiresChoosing the right tireBMW recommends winter tires – M+S
tires – for operation under inclement
winter driving conditions. While all-sea-
son tires – M+S designation – provide
better winter traction than the corre-
sponding summer tires, they generally
do not achieve the performance of win-
ter tires.
In the interest of safe tracking and
steering response, install winter tires
made by the same manufacturer and
with the same tread configuration on all
four wheels.
Never exceed the maximum
speed for which the winter tires
are rated.
Unprofessional attempts by laymen to
service tires can lead to damage and
accidents.
Have this work performed by trained
professionals only. Any BMW center
has the required technical knowledge
and the proper equipment and will be
happy to assist you.<
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131
Tire condition, tire pressureAt tread depths below approx.
3/16 in/4 mm, winter tires display a per-
ceptible decrease in their ability to cope
with winter driving conditions, and
should be replaced in the interest of
safety.
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.Snow chains*Only certain snow chains have been
tested by BMW and determined and
approved as roadworthy. Consult any
BMW center for details. BMW recom-
mends using only these approved fine-
link snow chains. Use them in pairs on
either summer or winter tires, but only
on both rear wheels.
Comply with all manufacturer's safety
precautions when mounting the chains.
Do not exceed a speed of 30 mph /
50 km/h when using snow chains.
You cannot mount snow chains with the
following tires:
225/50 R 16
225/45 R 17
225/40 R 18245/40 R 17
255/35 R 18Winter tires
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151
License plate lamps5 watt bulb
1. Place a screwdriver in the slot and
press toward the left – see arrow – to
release the lens
2. Replace the bulb.
Changing a wheel
Safety precautions in the event of
a flat tire or wheel change:
Stop the vehicle as far as possible from
passing traffic. Park on a firm, flat, sur-
face. Switch on the hazard warning
flashers. Turn the steering wheel to the
straight-ahead position and engage the
steering lock. Shift into 1st or Reverse,
or if you have an automatic transmis-
sion position the selector lever in Park,
and engage the parking brake.
All passengers should be outside the
vehicle and well away from your imme-
diate working area – behind a guardrail,
for example.
If a warning triangle or portable hazard
warning lamp is available, set it up on
the roadside at an appropriate distance
from the rear of the vehicle. Comply
with all safety guidelines and regula-
tions.
Change the wheel only on a level, firm
surface which is not slippery. Avoid
jacking the vehicle on a soft or slippery
support surface – snow, ice, loose
gravel, etc. – as either the vehicle or the
jack could slip sideways.
Position the jack on a firm support sur-
face.
Do not place wooden blocks or similar
objects under the jack. They could pre-
vent the jack from extending to its full
height and reduce its support capacity.
Do not lie under the vehicle or start the
engine when the vehicle is supported
by the jack. There is otherwise a risk of
fatal injury.<
Lamps and bulbs
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152
Your BMW is equipped with a space-
saver spare tire designed for temporary
use in maintaining the vehicle's mobility
in an emergency.
To remove the space-saver spare
tire, lift the floor panel in the lug-
gage compartment completely out,
refer to page 37.<
What you will needIn order to avoid rattling noises later,
note the position of the tools when you
remove them and return them to their
original position when you are through
using them.
>Jack 1
Raise the floor panel in the luggage
compartment, refer to page 37, and
undo the jack – see arrow.
When you have completed work, fold
the handle back and insert it in its
holder
>Chock 2
Located behind the jack on the wall
in the luggage compartment. Loosen
the wingnut to remove it
>Space-saver spare tire – next to jack
Loosen the wing nut – see arrow – by
hand, remove the storage shelf and
take the wheel out
>Lug wrench – in the onboard tool kit
on the underside of the luggage com-
partment lid, refer to page 146.Procedure1. Read and comply with the safety
precautions provided on the previ-
ous page
2. Secure the vehicle to prevent it
from rolling:
Place the chock against the rear
surface of the front tire on the side
opposite the side being raised. If
the vehicle is parked on a down-
ward slope, place the chock
securely in front of the tire. If the
Changing a wheel
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153
wheel must be changed on a sur-
face with a more severe slope, take
additional precautions to secure
the vehicle from rolling
3. Wheels with full wheel covers*:
reach into the ventilation openings
and pull the cover off
4. Loosen the lug bolts by rotating
half a turn
5. Position the jack at the jacking
point – see arrows – closest to the
flat tire with the jack base vertically
below the jacking point and the
entire surface of the head of the
jack moves into the square recess
of the jacking point when the jack
is cranked – refer to the detail in the
next illustration
6. Continue raising the vehicle up
until the wheel you are changing is
raised from the ground
7. Unscrew the lug bolts and remove
the wheel
8. Remove accumulations of mud and
dirt from the mounting surfaces of
the wheel and hub. Clean the lug
bolts
9. Position the new wheel or the
space saver spare tire on the hub
and screw at least two lug bolts fin-
ger-tight into opposite bolt holes
10. Screw in the remaining lug bolts.
Screw in all the bolts in a diagonal
pattern
11. Lower the jack and remove it from
beneath the vehicle
12. Tighten the lug bolts securely in a
diagonal pattern
Changing a wheel
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