Wheels and tyres
252Wear indicators
The original tyres on your vehicle have 1.6 mm high tread wear indicators
⇒ page 251, fig. 172 , running across the tread. Depending on the make,
there will be 6 to 8 of them evenly spaced around the tyre. Markings on the
tyre sidewall (for instance the letters “TWI” or other symbols) indicate the
positions of the tread wear indicators. The minimum tread depth required by
law is 1.6 mm (measured in the tread grooves next to the tread wear indica-
tors). Worn tyres must be replaced. Different figures may apply in export
countries ⇒.
Tyre pressure
Incorrect tyre pressure causes premature wear and could cause tyre blow-out.
For this reason, the tyre pressure should be checked at least once per month
⇒ page 249.
Driving style
Fast cornering, heavy acceleration and hard braking all increase tyre wear.
Changing wheels around
If the front tyres are worn considerably more than the rear ones it is advisable
to change them around as shown ⇒page 251, fig. 173. All the tyres will then
last for about the same time.
Wheel balance
The wheels on new vehicles are balanced. However, various factors encoun-
tered in normal driving can cause them to become unbalanced, which results
in steering vibration.
Unbalanced wheels should be rebalanced, as they otherwise cause excessive
wear on steering, suspension and tyres. A wheel must also be rebalanced
when a new tyre is fitted.
Incorrect wheel alignment
Incorrect wheel alignment causes excessive tyre wear, impairing the safety of
the vehicle. If tyres show excessive wear, you should have the wheel align-
ment checked by an Authorised Service Centre.
WARNING
There is a serious danger of accidents if a tyre bursts during driving!•The tyres must be replaced at the latest when the tread is worn down to
the tread wear indicators. Failure to do so could result in an accident. Worn
tyres do not grip well at high speeds on wet roads. There is also a greater
risk of aquaplaning.•At continuously high speeds, a tyre with insufficient pressure flexes
more. This causes it to overheat. This can cause tread separation and tyre
blow-out. Risk of accident. Always observe the recommended tyre pres-
sures.•I f t y r e s s h o w e x ce s s i v e w e a r, y o u s h o u l d h a v e t h e r u n n i n g g e a r ch e cke d
by an Authorised Service Centre.•Keep chemicals such as oil, fuel and brake fluid away from tyres.•Damaged wheels and tyres must be replaced immediately!For the sake of the environment
Under-inflated tyres will increase fuel consumption.Run-flat tyres
Run-flat tyres allow you to continue driving even with a punc-
tured tyre, in the majority of cases.In vehicles that are factory-fitted with run-flat tyres
25) the loss of tyre
pressure is indicated on the instrument panel.
25)Depending upon version and country.
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