width BMW 328Ci CONVERTIBLE 2000 E46 Owner's Manual

124n
To maintain good handling and vehicle
response, use only tires of a single
tread configuration from a single manu-
facturer. BMW tests and approves
wheel/tire combinations. Refer to
page 128.
DOT Quality GradesTreadwear
Traction AA A B C
Temperature A B C
In addition to the tire grades listed
above, all passenger car tires must
conform to Federal Safety Require-
ments as well.< TreadwearThe treadwear 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
characteristics 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 as-
phalt 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, corner-
ing, hydroplaning, or peak traction
characteristics.< TemperatureThe temperature grades are A (the high-
est), B, and C, representing the tire's re-
sistance to the generation of heat and
its ability to dissipate heat when tested
under controlled conditions on a speci-
fied indoor laboratory test wheel.
Sustained high temperature can cause
the tire material to degenerate and re-
duce tire life, and excessive tempera-
ture can lead to sudden tire failure. The
Grade C corresponds to a level of per-
formance which all passenger car 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 prop-
erly inflated and not overloaded. Exces-
sive speed, underinflation, or excessive
loading, either separately or in combina-
tion, can cause heat buildup and possi-
ble tire failure.< Uniform Tire Quality Grading Quality 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
Do not use retreaded tires ("caps").
Driving safety may be impaired by
their use. This due to the possible varia-
tions in casing structures and, in some
cases, to their extreme age, factors
which can lead to a decrease in their
durability.<
Tire replacement

126n
Wheel and tire combinations The right choice Use only tires approved by BMW.
Refer to the information beginning on
page 128.
Due to the high speeds this vehicle can
reach, the use of specific brands, spec-
ifications and sizes is mandatory. Con-
sult any BMW center for details.
Comply with local/national regulations.
The correct wheel-tire combina-
tion affects different systems, e.g.
ABS, ATC
* and DSC, whose function
would otherwise be impaired if im-
proper wheel-tire combinations are
used.
For this reason, use only tires of the
same brand and tread pattern. In the
event of a flat tire, for example, remount
the approved wheel-tire combination as
soon as possible.<
Codes on tires and wheels The tire codes will aid you in selecting
the correct tire.
The codes on radial tires:
The speed rating indicates the ap-
proved maximum speed for the tire.
Summer tires:
S = up to 112 mph (180 km/h)
T = up to 118 mph (190 km/h)
H = up to 130 mph (210 km/h)
V = up to 150 mph (240 km/h)
W = up to 167 mph (270 km/h)
Y = over 167 mph (270 km/h)
ZR = over 150 mph (240 km/h) For example:
Nominal width
in mm
Aspect ratio in X
Radial tire code
Rim diameter in inches
Load rating
(not on ZR tires)
Speed rating
(before R on ZR tires)
225/50 R
1692W
Winter tires:
Q M+S = up to 100 mph (160 km/h)
T M+S = up to 118 mph (190 km/h)
H M+S = up to 130 mph (210 km/h)
Codes stamped on light-alloy wheels:
Protect tire valves from dirt by using
screw-on valve stem caps. Dirt in the
valves frequently leads to slow leaks. For example:
Rim width
in inches
Code letter for
flange type
Symbol for full-drop
center rim
Rim diameter in inches
Hump on the 2 rim shoulders
7 x 16 H 2
J

Everything from A to Z
195n
IndexDataTechnologyRepairsCar careControlsOverview
Waxing, paintwork141
Weights184
Wheel lug wrench159
Wheel rims126
Wheelbase183
Wheels and tires126, 128
Width183
Wind deflector51
Windows
one-touch operation34
Windshield washer nozzle
adjustment132
Windshield washer reservoir,
filling132, 185
Windshield wiper77
blade replacement152
Winter operation118
Winter tires126, 127
Wiper system77
Work in the engine
compartment129XXenon lamp153, 179