BMW Z4 ROADSTER 2.5I 2005 E85 Manual Online

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Z4 2.5i
Z4 3.0i
Tire sizePressure specifications in psi/kPa
All pressure specifications in the table are
indicated in psi/kilopascal with cold tires,
cold = ambient temperature
225/50 R 16 92 V
225/45 R 17 91 W30/210 33/230
225/40 R 18 88 W 30/210 –
255/35 R 18 90 W – 33/230
205/55 R 16 91 Q/T/H M+S
225/50 R 16 92 Q/T/H M+S
225/45 R 17 91 Q/T/H M+S30/210 33/230
You will find more information about permissible loads and weights on page103.
Tire sizePressure specifications in psi/kPa
All pressure specifications in the table are
indicated in psi/kilopascal with cold tires,
cold = ambient temperature
225/45 R 17 91 W 33/230 36/250
225/40 R 18 88 W 33/230 –
255/35 R 18 90 W – 36/250
225/50 R 16 92 Q/T/H M+S
225/45 R 17 91 Q/T/H M+S33/230 36/250
You will find more information about permissible loads and weights on page103.

Wheels and tires
80
Tire coding
Understanding the lettering on the tire sidewall
makes it easier to identify and choose the cor-
rect tires.
Tire size
e.g. 225/50 R 16 92 V
Nominal width in mm
Cross-sectional
ratio in %
Radial belt construction
Rim diameter in inches
Load index,
not on ZR tires
Speed code letter,
in front of the R on ZR tires
Speed code letter
Q= up to 105 mph / 160 km/h
T= up to 118 mph / 190 km/h
H= up to 131 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
Tire Identification Number
Tires with DOT codes meet the guidelines of
the U.S. Department of Transportation.
DOT code:
e.g. DOT xxxx xxx 5004
Manufacturer's code
for tire brand
Tire size and
tire version
Tire age
Tire age
The date on which the tire was manufactured is
indicated by the code on the sidewall:
DOT … 5004 indicates that the tire was manu-
factured in week 50 of the year 2004.BMW recommends the replacement of all tires
every 6 years at the latest, even if a tire usage of
10 years is possible.
Uniform Tire Quality Grading
Quality grades can be found where applicable
on the tire sidewall between tread shoulder and
maximum section width. For example:
Treadwear 200 Traction AA
Temperature A
DOT quality grades
Tread wear
Traction AA A B C
Temperature A B C
All passenger car tires must conform to
Federal Safety Requirements in addition
to these grades.<
Tread wear
The tread wear grade is a comparative rating
based on the wear rate of the tire when tested
under controlled conditions on a specified gov-
ernment test course.
For example, a tire graded 150 would wear one
and one-half, 1 γ, times as well on the govern-
ment course as a tire graded 100. The relative
performance of tires depends upon the actual
conditions of their use, however, and may
depart significantly from the norm due to varia-
tions in driving habits, service practices and dif-
ferences in road characteristics and climate.
Traction
The 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 specified government test sur-
faces 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, cor-
nering, hydroplaning, or peak traction charac-
teristics.<

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Temperature
The 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 conditions
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 temperature can lead to
sudden tire failure. The grade C corresponds to
a level of performance which all passenger car
tires must meet under the Federal Motor Vehi-
cle 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,
under-inflation, or excessive loading, either
separately or in combination, can cause heat
buildup and possible tire failure.<
RSC: Run Flat tires
Run Flat tires are labeled on the sidewall with a
circular symbol containing the letters RSC.
Refer to page82.
M+S
Winter and all-season tires.
These have better winter performance proper-
ties than summer tires.
Tire condition
Inspect your tires frequently for tread wear,
signs of damage and for foreign objects lodged
in the tread. Check the tread depth.
Tire tread
Tread depth should not be allowed to go below
1/8 in / 3 mm even though in Europe, for exam-
ple, 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 very high risk of hydro-
planing, even with only small amounts of water
on the road and at relatively moderate speeds.At tread depths below approx. 1/6in/ 4mm,
winter tires display a perceptible decrease in
their ability to cope with winter driving condi-
tions, and should be replaced in the interest of
safety.
Tread wear indicators in the tread-groove base,
see arrow, are distributed around the wheel cir-
cumference and are labeled on the tire sidewall
as TWI, Tread Wear Indicator. At a tread depth
of 1/16 in / 1.6 mm, the indicators signal that the
legally permissible wear limit has been reached.
Wheel/tire damage
Due to low-profile tires, please note that
wheels, tires and suspension parts are
more susceptible to road hazards and conse-
quential damages.<
Unusual vibrations encountered during normal
vehicle operation can indicate tire failure or
some other vehicle malfunction. 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 pro-
nounced tendency to pull to the left or right.
Should this occur, respond by immedi-
ately reducing your speed. Proceed care-
fully to the nearest BMW center or professional
tire center, or have the vehicle towed there.
Tire damage up to and including sudden and
complete air loss can pose an extreme hazard
for both vehicle occupants and other road
users.<

Wheels and tires
82
Run Flat tires fitted
Run Flat tires are labeled on the sidewall with a
circular symbol containing the letters RSC.
Run Flat tires consist of self-supporting tires
and special rims. The tire reinforcement
ensures that driving remains possible to a
restricted degree in the event of pressure drop
or even if the tire is deflated.
Wheel and tire replacement
Have new wheels and tires mounted only
by a BMW center or specialized tire shop
that works according to BMW requirements
with the appropriately trained personnel. Work
that is improperly carried out could result in
consequential damage and pose safety haz-
ards. Make sure that the new wheels are bal-
anced.<
BMW advises against using retreaded
tires, since driving safety may be
impaired. This is due to possible variations in
casing structures and, in some cases, to their
extreme age, factors which can lead to a
decrease in their durability.<
The correct wheels and tires
BMW recommends using only wheels
and tires that have been approved by
BMW for your particular vehicle model, as oth-
erwise body contact and serious accidents can
result despite the use of the same nominal size,
e.g. due to manufacturing tolerances. If non-
approved wheels and tires are used, BMW can-
not evaluate their suitability, and therefore can-
not be held liable for driving safety.<Your BMW center can provide you with infor-
mation about the correct wheel and tire combi-
nations for your vehicle.
The correct wheel and tire combination also
affects other systems which would otherwise
be impaired, for example ABS or DSC.
To maintain good handling and vehicle
response, use only tires of a single brand and
tread configuration. In the event of a flat tire,
remount the previous wheel and tire combina-
tion as soon as possible.
Recommended tire brands
BMW tests certain tire brands for each tire size,
classifies them as road-safe and approves
them. You can best find out about these at a
specialized shop, particularly your BMW center.
Observe any country-specific regulations, e.g.
on making a corresponding entry in the vehicle
documents.
The factory-approved radial-ply tires are
matched to your vehicle and have been
selected to provide optimum safety and driving
comfort when used properly.
Run Flat tires
When mounting new tires or replacing summer
tires with winter tires, or vice versa, use Run Flat
tires since no spare wheel is available in the
event of a flat. Your BMW center will be glad to
provide you with more information.
For safety reasons, BMW recommends to
have Run Flat tires replaced, not repaired,
if they are damaged.<
Special characteristics of winter tires
BMW recommends the use of winter tires for
operation under winter road conditions. While
all-season tires with M+S designation provide
better winter traction than summer tires, they
generally do not achieve the full performance of
winter tires.
Observing speed ratings
Never exceed the maximum speed for
which the winter tires are rated. Unpro-
fessional attempts by laymen to service tires

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can lead to damage and accidents. Have this
work performed by skilled professionals only.
The technicans at your BMW center will be glad
to assist you with the required professional
knowledge and specialized equipment.<
Storage
Store tires in a cool, dry place, protecting them
against light whenever possible. Protect the
tires from contact with oil, grease and fuel. Do
not exceed the maximum tire inflation pres-
sures specified on the tire sidewall.
Snow chains*
Only certain types of snow chains have been
tested by BMW, classified as road-safe and
approved. Consult your BMW center for more
information. BMW recommends using only
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 precau-
tions when mounting the chains.
Do not exceed a speed of 30 mph / 50 km/h
when using snow chains.
Do not initialize the Flat Tire Monitor after
snow chains have been mounted.
When driving with snow chains, it may be useful
to deactivate the DSC briefly. Refer to
page51.<

In the engine compartment
84
In the engine compartment
Do not attempt to service your vehicle if
you do not have the required technical
background. If you are not familiar with the reg-
ulations to be observed, have your vehicle ser-
viced only by a BMW center or a workshop that
works according to BMW requirements with the
appropriately trained personnel. Work that is
improperly carried out could result in conse-
quential damage and pose safety hazards.<
Hood
To release
Pull the lever located under the left-hand side of
the instrument panel.
To open
1.Reach under the engine hood
2.Push the release handle up
3.Open the hood.
To close
Allow the hood to fall from a low height and
push on both sides so that it audibly engages.
As in all closing procedures, avoid injuries
by making sure that the travel path of the
hood is clear when it is closed.
If you notice while driving that the hood is not
completely closed, stop immediately and close
it securely.<

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Engine compartment
1Reservoir for the headlamp and windshield
washer system86
2Engine oil filler neck87
3Auxiliary terminal for jump-starting974Reservoir for brake fluid88
5Chassis ground, negative terminal
6Engine oil dipstick86
7Coolant expansion tank87

In the engine compartment
86
Washer fluids for washer
systems
Headlamp* and windshield washer
system
Capacity of windshield washer system: approx.
3.2 quarts/3 liters.
Capacity when equipped with headlamp
washer system: approx. 5.3 quarts/5 liters.
Fill with water and, if required, with an antifreeze
agent according to the manufacturer's recom-
mendations.
We recommend that you mix the washer
fluid before adding it to the reservoir.<
Antifreeze agents for the washing sys-
tems are highly flammable. For this rea-
son, keep them away from sources of flame and
store them only in their original containers.
Store them so that they are inaccessible to chil-
dren. Comply with the instructions on the con-
tainers.<
Engine oil
Oil consumption is directly influenced by your
driving style and vehicle operating conditions.
Warning lamp
Engine oil pressure
The warning lamp lights up in red:
The engine oil pressure is too low.
Stop the vehicle immediately and
switch off the engine. Check the engine oil level
and top up if necessary. If the oil level is correct,
please contact the nearest BMW center.Do not continue driving, as the engine
could sustain serious damage from inad-
equate lubrication.<
Engine oil level
The warning lamp lights up in yellow
while driving:
The oil level is at the absolute mini-
mum; refill as soon as possible. Do not drive
more than 30 miles/50 km before refilling.
The warning lamp lights up in yellow
after the engine has been switched off:
Add engine oil at the earliest opportu-
nity, e.g. when you stop to refuel.
Engine oil sensor
The warning lamp lights up in yellow
within 20 seconds after the engine is
started:
The oil level sensor is defective. Please have it
checked by a BMW center.
Checking the oil level
1.With the vehicle's engine at normal operat-
ing temperature, i.e. after uninterrupted
driving for at least 6 miles/10 km, park the
vehicle on a level surface
2.Switch off the engine
3.After approx. 5 minutes, pull the dipstick
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

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6.Return the dipstick to the guide tube,
inserting it as far as it will go.
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 quarts/
1 liter.
Do not fill beyond the upper mark on the
dipstick. Excess oil will damage the
engine.<
Adding engine oil
Do not add oil until the oil level has dropped
almost to the lower mark on the dipstick, refer to
page86.
Add oil within the next 30 miles/50 km,
otherwise the engine could be dam-
aged.<
Continuous exposure to used oil has
caused cancer in laboratory tests. For this
reason, thoroughly wash any areas of skin that
come into contact with oil using soap and water.
Always store oils, grease and similar materials
so that they are inaccessible to children. Com-
ply with warning labels and the information on
the containers.<
Comply with the applicable environmen-
tal laws regulating the disposal of used
oil.<
Oil change
Have your oil changed only by a BMW center or
a workshop that works according to BMW
requirements with the appropriately trained
personnel.
Approved engine oils
The quality of the engine oil is extremely impor-
tant for the function and life of an engine. Based
on extensive testing, BMW has approved cer-
tain grades of engine oil.
Use approved High Performance Synthetic Oil.
If you are unable to obtain an approved High
Performance Synthetic Oil, you may use small
volumes of other synthetic oils for topping up
between oil changes. Use only oils with the
specification API SH or higher.
Ask your BMW center for details concern-
ing the specific High Performance Syn-
thetic Oil or synthetic 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 information.
BMW engines are designed to operate
without oil additives; the use of additives
could even lead to damage in some cases.<
Coolant
Warning lamp
The warning lamp lights up:
The coolant level is too low. Top up the
coolant as soon as possible.
Do not open the cooling system when the
engine is hot. If you do, escaping coolant
can cause burns.<
Coolant consists of water and coolant additives.
Not all commercially available additives are suit-
able for your BMW. Your BMW center knows
which additives are appropriate.
Use only approved additives, as the
engine could otherwise be damaged. The
additives are hazardous to health.<
Comply with the applicable environmen-
tal laws regulating the disposal of coolant
additives.<

In the engine compartment
88
Checking the coolant level
1.The engine must be at ambient tempera-
ture
2.Open the cap of the expansion tank by turn-
ing it slightly counterclockwise to allow
accumulated pressure to escape, then
open completely
3.The coolant level is correct when the upper
end of the red float is at least even with the
upper edge of the filler neck but no more
than 3/4 in/2 cm above it, that is up to the
second mark on the float. Refer also to the
schematic diagram next to the filler neck
4.Slowly add coolant, if necessary, until the
correct level is reached; do not overfill
5.Turn the cap clockwise until it is tightly
closed
6.Have the cause for the coolant loss
removed as soon as possible.
Brake system
Malfunction
Brake fluid
The warning lamp lights up although
the parking brake is not engaged:
Stop the vehicle immediately.
The brake fluid level in the reservoir is too low.
At the same time, you may notice that brake
pedal travel is longer. Have the system checked
as soon as possible.
If you continue driving, extended pedal
travel may be necessary and braking dis-
tances may be significantly longer. Be sure to
adapt your driving style accordingly.<Indication of the above-described mal-
function in Canadian models.
Brake pads
The warning lamp lights up. The brake
pads have worn down to the minimum
safe limit. Have the brake pads
replaced as soon as possible.
For your own safety: use only brake pads
which BMW has approved for your spe-
cific vehicle model. BMW cannot evaluate non-
approved brake pads to determine if they are
suitable for use, and therefore cannot guaran-
tee the operating safety of the vehicle in the
event of their use.<