Wheels and Tyres
242
•
The wheel bolts must be clean and must
turn easily. However, they must
never be treated with grease or oil.•
If the wheel bolts are tightened to a too low tightening torque, the rim
can lossen when the car is moving - risk of accident! A tightening torque which is too high can damage the bolts and threads and this can result in permanent deformation of the contact surfaces on the rims.
Caution
The prescribed tightening torque of the wheel bolts for steel and light alloy wheels is 120 Nm.Winter tyresThe handling of your vehicle will be signi
ficantly improved when driving on wintry
roads if you fit winter tyres. Summer tyres do not offer the same grip on ice, snow and at temperatures below 7 °C because of
their construction (width, rubber blend,
tread pattern). This particularly applie
s to vehicles which
are equipped with
low-
profile tyres
or high-speed tyres
(code index H or V on wall of tyre).
Winter tyres must be mounted on all four
wheels to obtain the
best handling char-
acteristics. You must only fit those types of winter tyre
which are approved for your vehicle. The
permissible
sizes of winter tyres
are stated in your vehicle documents. Approvals
may differ because of
national legislation.
Please remember that the tyres should be in
flated to 20 kPa (0.2 bar) more than is
the case for summer tyres
⇒page 238.
Winter tyres no longer offer the
same winter performance once the
tyre tread
has
worn down to a depth of about 4 mm. Ageing
a l s o c a u s e s w i n t e r t y re s t o l o s e m o s t
of their winter performance properties
- even in cases where the remaining tread depth is still clearly more than 4 mm. Speed restrictions
apply to winter tyres as
well as to summer tyres
⇒page 240,
⇒
.
You can fit winter tyres of a lower speed ca
tegory to your vehicle provided that you
also do not drive faster than the permissible maximum speed for such tyres, even if the possible maximum speed of your ve
hicle is higher. The
corresponding tyre
category can damage the tyres when ex
ceeding the permissible maximum speed.
Please pay attention to the notes if
you decide to fit winter tyres
⇒page 238.
You can also fit so-called “all-year tyres” instead of winter tyres.Please contact your specialist garage if there are any points which are not clear who will be able to provide you with information regarding the maximum speed for your tyres.
WARNING
You must on no account drive your car at more than the permissible maximum speed for your winter tyres -
risk of an accident resulting from
tyre damage and loss of control over your car.
For the sake of the environment
Fit your summer tyres on again in good time since summer tyres offer you better grip and handling on roads which are free of snow and ice as well as ar tempera- tures below 7 °C - the braking distance is shorter, there is less tyre noise, tyre wear is reduced and fuel consumption is reduced.
Note
Please observe the various differing legal requirements regarding tyres.Unidirectional tyres*The direction of rotation of the tyres is marked by
arrows on the wall of the tyre
.
This indicates the direction of
rotation of the tyre, and it is essential that the tyres
are fitted on to run in this direction. On
ly then are the tyres able to provide the
optimal properties in terms of grip, lo
w noise, wear-and-tear and aquaplaning.
Should it be necessary to fit on a spare
wheel in exceptional cases with a tyre not
dedicated to the running direction or in o
pposite running direct
ion, please adopt a
WARNING (continued)
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