198Wheels and tyres
Unusual vibration or the car pulling to one side may indicate that one of the
tyres is damaged. Reduce speed immediately and stop if you suspect that
damage may have occurred! Check the tyres for damage (blisters, cracks,
etc.). If no external damage is visible, drive slowly and carefully to the near-
est Official Service and have the vehicle inspected.
Handling wheels and tyres
Fig. 132 Changing
wheels around
Changing wheels around
If the wear is visibly greater on the front tyres, they should be exchanged for
the rear tyres as shown in the diagram ⇒ Fig. 132. All the tyres will then last
for about the same time.
To ensure that the wear is equal on all tyres and maintain their optimum
useful life, they should be changed around every 10 000 km (6000 miles).
Storing tyres
When you remove the tyres, mark them in order to maintain the same direc-
tion of rotation when they are installed again.
When removed, the wheels and/or tyres should be stored in a cool, dry and
preferably dark location. Store tyres in a vertical position if they are not fit-
ted on wheel rims. Replacing tyres and wheels
All four wheels must be fitted only with tyres of the same type, size and the
same tread pattern.
The correct tyre/wheel combinations specified for your vehicle are listed in
its registration documentation.
Understanding the tyre designations makes it easier to choose the correct
tyres. The tyre designation is marked on the sidewall. For example.
195/55 R 15 85 H
This contains the following information:
195Tyre width in mm55Height/width ratio in %RTyre construction – Radial15Rim diameter in inches85Load rating codeHSpeed rating code letter
The tyres are subject to the following maximum speed limits:
Speed rating code letterMaximum speed limitQ160 km/h (99 mph)R170 km/h (106 mph)S180 km/h (112 mph)T190 km/h (118 mph)U200 km/h (124 mph)H210 km/h (130 mph)V240 km/h (149 mph)W270 km/h (168 mph)
202Wheels and tyres
WARNING
● If the warning lamp lights up, slow down immediately and avoid
any severe braking or steering manoeuvres. Stop and check the tyres and
their pressure as soon as possible.
● Under certain conditions (e.g. sporty driving style, driving on loose
surfaces or in the winter) the warning lamp may take a while to light
up or may remain switched off.
● Despite the tyre pressure monitoring system, the driver remains re-
sponsible for maintaining the correct tyre pressure. You must therefore
check the tyre pressure often.
Note
● The tyre pressure monitoring system is not a replacement for regularly
checking the tyre pressure, as it is unable to recognise an even drop in pres-
sure.
● The tyre pressure monitoring system is unable to warn of a sudden drop
in tyre pressure, e.g. a puncture. In this case, try to stop the vehicle carefully
with no severe braking or steering manoeuvres.
● To ensure the tyre pressure monitoring system works correctly, the basic
setting must be performed every 10 000 km (6000 miles) or once a year.
Wheel bolts
The wheel bolts are matched to the rims. When installing different wheels,
e.g. to fit light alloy wheels or wheels with winter tyres, it is important to use
the correct wheel bolts with the right length and correctly shaped bolt
heads. The is essential for the secure fit of the wheels and for the proper
function of the brake system. Winter tyres
Winter tyres will significantly improve handling of the vehicle in winter road
conditions. The design of summer tyres (width, rubber compound, tread
pattern) gives less grip at temperatures below +7 °C (45 °F), on ice and
snow. This applies particularly to vehicles equipped with
wide section tyres
or high speed tyres (code letters H or V on the sidewall).
In order to preserve the performance of the vehicle as much as possible,
winter tyres must be fitted on all four wheels, the minimum depth of the
tread must be 4 mm and the maximum age must be 4 years.
You can use winter tyres of a lower speed rating if the maximum speed limit
of these tyres will not be exceeded, even if the maximum speed limit for the
vehicle is higher.
For the sake of the environment
Summer tyres should be fitted again in time, as they give better handling on
roads free of snow and ice and at temperatures over +7 °C (45 °F). Summer
tyres have a shorter braking distance, produce less rolling noise and do not
wear down as quickly. They also reduce fuel consumption.
Snow chains
Snow chains must only be used on the front wheels.
In winter road conditions, snow chains not only help to improve grip but al-
so improve the braking capacity.
For technical reasons snow chains may only be used on tyres with the fol-
lowing wheel rim/tyre combinations.
