2001 BMW Z8 tire type

20n

Indicator and warning lamps

Technology that monitors itself

Many of the systems for your BMW
monitor themselves automatically, both
during engine starts and while you are
driving. Indicator and warning lamps
identified by "

l

" are tested for proper
operation whenever the ignition key is
turned. They each light up once for
different periods of time.
The indicator lamps signal defects in
monitored systems either by remaining
lit after the engine is started or by
coming on in the course of normal
vehicle operation. Refer to the following
section for detailed information on how
to respond to the various types of warn-
ings.

Red: stop immediately

Battery charge current
The alternator is no longer
charging the battery. Indicates a
defect in the alternator drive belt or the
charging circuit. Please contact the
nearest BMW center.
Never attempt to continue driving
if the V-belt is defective: the
engine could overheat and sustain
serious damage. A broken or damaged
V-belt will also lead to a sudden
increase in steering effort.

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Engine oil pressure

l

Stop vehicle and switch off
engine immediately. Check the
engine oil level and top up as required.
If the oil level is correct, please contact
the nearest BMW center.
Do not continue driving. The
engine could sustain damage
owing to inadequate lubrication.

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Tire Pressure Warning (RDW)

l

Flashing warning lamp in addi-
tion to an acoustic signal: a tire
failure has occurred. Carefully reduce
speed to less than 50 mph (80 km/h),
and avoid hard braking or steering
maneuvers.
For additional information, refer to
page 67.
Brake warning lamp

l

If the lamp comes on when the
parking brake is not engaged,
check the brake fluid level. Before
driving further, be sure to read the
notes on pages 91 and 112.
Brake warning lamp for Cana-
dian models.

88n
Antilock Brake System (ABS) The concept ABS enhances active safety by helping
to prevent the wheels from locking
under braking. Why is this important?
When front wheels lock up and cease
to turn, the tires break into a slide.
Result: the driver loses the ability to
steer the vehicle. Traction loss at the
rear wheels can cause the back end of
the car to slip sideways and break away
in uncontrolled oversteer.
With ABS, you will achieve the shortest-
possible braking distances under all
given conditions (braking while driving
straight ahead or in curves, different
road surfaces).
ABS is designed to meet two essential
requirements during every brake appli-
cation:
>To help provide vehicle stability
>To help retain steering and maneu-
vering capability on all types of road
surfaces (asphalt, concrete, dirt, wet
surfaces, snow and ice).
Braking with ABSThe system is operative once the
vehicle exceeds a speed of approx.
6 mph (10 km/h). The ABS is deacti-
vated whenever the vehicle's speed
drops back below approx. 4 mph
(6 km/h). This means that the wheels
can lock only in the final phase of a
panic stop Ð a factor of no substantive
significance in actual use.
The ABS system works best in situa-
tions requiring maximum pressure on
the pedal (full braking). Since the
vehicle maintains steering responsive-
ness, you can nevertheless avoid
possible obstacles with a minimum of
steering effort.
The ABS system's closed-loop control
circuit cycles in fractions of a second.
A pulsing of the brake pedal, combined
with the sounds associated with the
hydraulic controls, tells you that the
brake system is within its maximum
limit range and reminds you that you
should adapt your vehicle's speed to
road conditions.On road surfaces that have a loose layer
on a firm base (on gravel or snow, for
instance), the braking distances with
ABS may be longer than with the wheels
locked. This also applies for driving with
snow chains. However, ABS continues
to provide enhanced vehicle stability
and steering response under these
conditions.

101n
IndexDataTechnologyRepairsCar careControlsOverview
Wheel and tire combinations The right choice
Use only wheels and tires
approved by BMW for the corre-
sponding vehicle model, as otherwise
the tires may make contact with the
body as the result of tolerances despite
the same nominal size being used,
resulting in serious accidents. If non-
approved wheels and tires are used,
BMW cannot evaluate their suitability,
and therefore cannot be held liable for
driving safety.<
For wheel and tire specifications
approved by BMW, refer to page 103.
The correct wheel-tire combina-
tion affects different systems that
otherwise will not function properly,
e.g. ABS, DSC and RDW.
For this reason, use only tires of the
same brand and tread pattern on the
vehicle and, for example, restore the
approved wheel-tire combination
following a flat tire as soon as
possible.<
Codes on tires and wheels The code on tires has the following
meaning.
Codes on radial tires:
The speed rating indicates the approved
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 = up to 186 mph (300 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)
245/45 R 18 96 W
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 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.
Tires with emergency driving character-
istics also possess an additional identi-
fication mark that varies by manufac-
turer, e. g.:
Bridgestone RFT
Dunlop DSST
Goodyear EMT
Michelin ZPStorage Store tires in a cool, dry place,
protecting them against light when-
ever possible. Protect the tires against
contact with oil, grease and fuel. 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
8x18EH 2
J

103n
IndexDataTechnologyRepairsCar careControlsOverview
Approved wheel and tire specifications Snow chains
*
It is impossible to install snow chains
when using summer tires
275/40 R 18 99 W.
Do not activate the RDW system
while using snow chains.
Malfunction warnings and undetected
losses in pressure are possible when
driving with snow chains.
For further information, refer to
page 67.< BMW tests certain tire brands for each tire size, classifies them as road-safe and
approves them. Your BMW center can provide further information.
Observe any regulations applicable in the country of use, e.g. requiring entry in
the vehicle documents.
Tire specifications Light-alloy wheel
BMW Z8
Summer tires
Front: 245/45 R 18 96 W 8Jx18EH2
Rear: 275/40 R 18 99 W 9Jx18EH2
Winter tires
245/45 R 18 96 H M+S 8Jx18EH2
The use of rims and wheel bolts
that do not meet the specifications
of the original factory-installed equip-
ment 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 control.<