Checking the tread depth
T
read depth
Most driving situations require the highest
possible tread depth. The tyres should have
the same tread depth, at the minimum on
each axle →
. This is especially true in
wet or wintry roa
d conditions.
In most countries, the minimum tread
depth required by law is 1.6 mm (1/16 in),
measured in the tread grooves next to the
tread wear indicators. Observe any deviat-
ing country-specific legal requirements.
Observe any country-specific legal require-
ments relating to the permissible minimum
tread depths for winter and all-year tyres.
Tyre wear
The tyre wear is aected by several factors:
— Style of driving.
— How well the tyres are balanced.
— Adjustments made to the running gear.
Wheel imbalance may develop when the
vehicle is driven; you will notice this by the
nervous steering response. Imbalanced
tyres will aect the level of tyre wear. In
this case the wheels should be balanced
again.
Incorrect wheel alignment causes exces-
sive tyre wear, impairing the safety of the
vehicle. The wheel alignment should be
checked by a suitably qualified workshop if
tyres show excessive wear.
Tyre wear with a sporty driving style
Fast cornering, heavy acceleration and hard
braking all increase tyre wear.
If you adopt a sporty driving style, check
the tread depth every 5,000 to 10,000 km
(approx. 3,107 to 6,214 mi).
Tread wear indicators in tyres
Fig. 214 In the trea
d grooves: tread wear in-
dicators.
There are 1.6 mm (1/16 in) high wear indica-
tors → Fig. 214 in the tread base of the
tyres. Markings on the tyre sidewall indicate
the position of the tread wear indicators
→ Fig. 214.
The tread wear indicators show if a tyre is
worn down. The tyre must be replaced at
the latest when the tread depth is just
down to the tread wear indicator.
When the tread depth is checked, the wear
indicators of all tread grooves must be
checked.
WARNING
Worn tyres are a safety risk and make it
dic
ult to control the vehicle properly;
they also increase the braking distance
and the risk of skidding.
Worn tyres have a greatly reduced grip.
The vehicle is more likely to lose its grip
on wet roads in particular (aquaplaning).
Worn tyres can lead to loss of vehicle
control, serious accidents and fatal inju-
ries.
·
If the tyres have worn down to the
tread wear indicator, replace the tyres
with new tyres.
Wheels and tyres in snow and
ic
e
Winter tyres
S
ummer tyres have less grip on icy or
snow-covered roads. Winter or all-season
Wheels and tyres in snow and ice
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