
Wheels and Tyres223
Using the systemSafetyDriving TipsGeneral MaintenanceBreakdown assistanceTechnical Data
Wheels and Tyres
Wheels
General comments
•New tyres do not offer optimal grip at first and should therefore be run in for
about 500 km at a moderate speed and an appropriately cautious style of driving.
You will also profit from longer tyre life.
•The tread depth of new tyres may differ because of design features and the
configuration of the tread (depending on the type of tyre and the manufacturer).
•Drive over curbs on the side of the road and other such obstacles slowly and,
where possible, at a right angles in order to avoid damage to tyres and wheel trims.
•Inspect your tyres from time to time for damage (punctures, cuts, splits and
bulges). Remove foreign bodies from the tyre profile.
•Damage to tyres and wheels is frequent ly not visible. Unusual vibrations or
pulling of the vehicle to one side could be a sign of tyre damage. Please reduce
your speed immediately and stop if you suspect that a wheel is damaged.
Inspect the tyres for signs of damage (bulge s, splits, etc.) If no visible damage is
present, please drive at an appropriatel y slow speed and carefully to the nearest
specialist garage in order to have your vehicle inspected.
•Also protect your tyres from contact with oil, grease and fuel.
•Immediately replace any dust caps of the valves which have got lost.
•Mark wheels before removing them so th at their previous direction of running
can be maintained when mounted them again.
•Always store wheels or tyres which been removed in a cool, dry and, where
possible, dark place. Tyres which are not fixed to a wheel trim should be stored
upright.
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. Only then are the tyres able to provide the optimal
properties in terms of grip, low noise, wear-and-tear and aquaplaning. Further information concerning
the use of unidirectional tyres ⇒page 227.
WARNING
•New tyres during the first 500 km do not offer optimal grip and should
therefore be run appropriately - risk of accident!
•Never drive with damaged tyres - risk of accident!
Note
Please observe the various differing legal requirements regarding tyres.
Tyre life
The life of your tyres very much depends on the following points:
Tyre pressure
The working life of tyres will be shortened considerably if the tyres are insufficiently
or over-inflated and this will have an adverse effect on the handling of your vehicle.
Correctly inflated tyres are of partic ular importance when travelling at high speeds.
It is therefore good to check the pressure at least once a month and also before
Fig. 204 An opened fuel
filler flap with the tyre
inflation pressure table
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Wheels and Tyres
224
setting off on a long trip. Please do not forget the spare wheel when checking the
tyres.
The tyre inflation pressures for summer tyres are indicated on the inside of the fuel
filler flap ⇒page 223, fig. 204 . The inflation pressures for winter tyres are 20 kPa
(0.2 bar) higher than those for summer tyres ⇒page 227.
The tyre pressure should be at the highest pressure specified for your vehicle at all
times.
The tyre inflation pressure of the emergency spare wheel R 18 is 420 kPa (4.2 bar).
Always check the inflation pressure of ty res when cold. Do not reduce the higher
pressure of warm tyres. Adapt the inflation pressure of the tyres accordingly if your
vehicle is carrying a significantly higher payload.
Driving style
Fast cornering, sharp acceleration and braking (squealing tyres) increase wear-and-
tear on your tyres.
Balancing wheels
The wheels of a new vehicle are balanced. There are a wide range of influences
when driving which may result in an imbalance and which makes themselves felt
through vibration in the steering.
You should have the wheels rebalanced since any imbalance increases wear-and-
tear on the steering, the suspension and tyres. A wheel must also be rebalanced
when a new tyre is fitted and each time a tyre is repaired.
Wheel alignment errors
Incorrect wheel alignment at the front and re ar will not only increase wear-and-tear
on the tyres but will also has an adverse effect on vehicle safety. Contact your
specialist garage if you notice any unusual tyre wear.
WARNING
If the inflation pressure is too low, the tyre must perform a greater flexing
work. At higher speeds the tyre will warm up as a result of this. This can
result in tread separation and even a tyre blowout.
•Immediately replace the damaged rims or tyres.
For the sake of the environment
Tyres which are insufficiently inflated increase your fuel consumption.
Wear indicators
The base of the tread of the original tyres has wear indicators 1.6 mm high, installed
at right angles to the direction of travel. These wear indicators are located at 6 - 8
points depending on the make and are evenly spaced around the circumference of
the tyre ⇒fig. 205 . Markings on the walls of the tyres through the letters “TWI”,
triangular symbols or other symbols identi fy the position of the wear indicators.
A remaining tread of just 1.6 mm, measured in the grooves of the tread next to the
wear indicators, means that your tyres have reached their legally permissible
minimum tread depth.
WARNING
•You must have your tyres replaced with new ones at the latest when the
wear indicators have been worn do wn. The legally permissible minimum
tread depth should be observed.
•Worn tyres do not provide the necessary adhesion to the road surface at
high speeds on wet roads. One could experience “aquaplaning” (uncon-
trolled movements of the vehicle - “swimming” on a wet road surface).
Fig. 205 Tyre tread with
wear indicators
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Breakdown assistance
232
The fire extinguisher must be checked by an authorised person or company annu-
ally (please observe the differing legal requirements).
WARNING
If the fire extinguisher is not correc tly attached, in case of sudden manoeu-
vres or an accident it can be “thrown” through the interior compartment and
cause injuries.
Note
•The fire extinguisher must comply with the relevant and valid legal require-
ments.
•Pay attention to the expiration date of the fire extinguisher. If the fire extin-
guisher is used after the expiration date, its proper function is no longer assured.
•The fire extinguisher is only supplied in certain countries within the scope of
delivery.
Vehicle tool kit
The vehicle tool kit and the li fting jack are stored in a locable box in the spare wheel
⇒ fig. 209 . There is also space here for the removable ball for the trailer towing
device*. The box is attached wi th a strap on the spare wheel.
The vehicle tool kit contains the following parts (depending on equipment fitted):
•Hook for pulling off a full wheel trim,
•Plastic clip for a wheel bolt cover,
•Wheel wrench,
•To w i n g e y e ,
•Adapter for the wheel bolts lock.
After using the lifting jack, screw in the arm of the lifting jack fully before placing it
back in its stowage area.
WARNING
•The factory-supplied lifting jack is only intended for your model of
vehicle. On no account attempt to lift a heavier vehicle or other loads - risk
of injury!
•Ensure that the vehicle tool kit is safely attached in the luggage compart-
ment.
Note
Ensure that the box is alwa ys secured with the strap.
Tyre repair kit*
The tyre repair kit is intended for the repair of minor tyre defects. The tyre repair kit
contains a compressor, inflation bottle, operating instructions and accessories.
The repair with the tyre repair kit is not at all intended to replace a permanent
repair on the tyre, this repair only serves to reach the next specialist garage. The
repair can be undertaken on the vehicle immediately. Please read the attached
instructions carefully before the repair.
Fig. 209 Luggage
compartment: Storage
compartment for vehicle
too kit
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