BMW 325Ci COUPE 2003 E46 Owner's Manual

111 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 fre-
quent cause of tire damage. It also sig-
nificantly influences the roadholding
ability of your BMW.
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 24. If this is not done,
incorrect tire pressures can cause driv-
ing instability and tire damage, ulti-
mately 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 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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112
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.<Tread wearThe tread wear grade is a comparative
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.<TemperatureThe temperature grades are A, the
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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113
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.<Uniform Tire Quality GradingQuality grades can be found where
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 the Flat Tire Monitor or
Tire Pressure Monitor (TPM), which
indicate a flat tire.
For additional information on the Flat
Tire Monitor or Tire Pressure Monitor
refer to page 81 or 82.
Run Flat tires are only possible in
conjunction with the Flat Tire
Monitor or Tire Pressure Monitor.<
Tire replacement
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114
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.<
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.
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
having 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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115
Tire condition, tire pressureAt tread depths below approx. 3/16 in /
4 mm, winter tires display a perceptible
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*BMW has assessed the safe perfor-
mance of certain specific tire brands
and approved them for use. Consult
any BMW center for details. BMW rec-
ommends using approved fine-link
snow chains only. Use them inpairs 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 on the
following tires:
225/50 R 16
225/45 R 17
225/40 R 18
245/40 R 17255/35 R 18Winter tires
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116In 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, please have the opera-
tions performed by your BMW center.<
To openPull the release handle and open the
hood.
To closeAllow the hood to fall from a height of
about 1 ft/30 cm so that it audibly
engages.
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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Engine compartment essentials
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119
1Brake fluid reservoir123
2Engine oil dipstick120
3Coolant expansion tank122
4Reservoir for the headlamp and
windshield washer system120
5Engine oil filler neck121
6Auxiliary terminal for jump-
starting141Engine compartment essentials
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Washer fluidsHeadlamp* and windshield
washer systemCapacity approx. 5.6 US quarts/
5.3 liters
Fill with water and – if required – with a
washer antifreeze additive according to
manufacturer's recommendations.
We recommend that you mix the
washer fluid before adding it to
the reservoir.<
Antifreeze agents for the washer
fluid are highly flammable. For this
reason, keep them away from sources
of flame and store them only in closed
original containers, inaccessible to chil-
dren. Comply with the instructions on
the containers.<
Engine oilChecking the oil level1. Park the vehicle on a level surface
2. Switch the engine off after it has
reached normal operating tempera-
ture
3. After approx. 5 minutes, pull the dip-
stick out and wipe it off with a clean
lint-free cloth, paper towel, or similar
material
4. Carefully push the dipstick all the
way into the guide tube and pull it
out again
5. The oil level should be between the
two marks on the dipstick.
As with fuel economy, oil consumption
is directly influenced by your driving
style and vehicle operating conditions.
The oil volume between the two marks
on the dipstick corresponds to approx.
1.1 US quarts/1 liter. Do not fill beyond
the upper mark on the dipstick. Excess
oil will damage the engine.
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