Volvo S40 Owner's Manual page 158

More even wear and maintenance
Tread wear indicators
The correct tyre pressure results in more
even wear, see page 161. To achieve the
best traction and more even wear on the
tyres, the regular switching of the front and
rear tyres with each other is recommended.
The first change should be after 5000 km and
then at intervals of 10000 km, this is to avoid
differences in tread depth. Tyres with the
greatest tread depth should always be fitted
to the rear wheels to decrease the risk of
skidding. Contact an authorised Volvo work-
shop for an inspection if you are uncertain
about tread depth.
Wheels should be stored lying down or
hanging up, and not standing up.
Tyres with tread wear indicators
Tread wear indicators are narrow treadless
bands across the width of the tread. On the
side of the tyre are the letters TWI (Tread
Wear Indicator). When the tyre's tread depth
is down to 1.6 mm, the tread depth will be
level in height with the tread wear indicators.
Change to new tyres as soon as possible.
Remember that tyres with little tread depth
provide very poor grip in rain and snow.
Winter tyres
Volvo recommends winter tyres with particu-
lar dimensions. These are stated on the tyre
pressure label, see page 160 for its location.
The tyre dimensions are dependent on the
engine variant. When driving on winter tyres,
these must be fitted to all four wheels.
NOTE
Ask a Volvo dealer which rim and tyre types
are most suitable.
Studded tyres
Studded winter tyres should be run in gently
for 500–1000 km so the studs settle properly
into the tyre. This gives the tyre, and
especially the studs, a longer lifespan.
07 Wheels and tyres
NOTE
The legal provisions for the use of studded
tyres vary from country to country.
Tread depth
Road conditions with ice, slush and low tem-
peratures place considerably higher
demands on tyres than summer conditions. It
is therefore not recommended to drive on
winter tyres that have a tread depth of less
than four millimetres.
Snow chains
Snow chains may only be used on the front
wheels. This also applies to all-wheel-drive
cars.
Never drive faster than 50 km/h with snow
chains. Avoid driving on bare ground as this
wears out both the snow chains and tyres.
Never use quick-fit snow chains as the space
between the brake discs and the wheels is
too small.
IMPORTANT
Use Volvo genuine snow chains or equiva-
lent chains designed for the car model, and
tyre and rim dimensions. Consult an author-
ised Volvo workshop.
General
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