Wheels and tires, Tire inflation pressure, Tire condition – BMW 330XI User Manual

Page 117

117

Wheels and tires

Tire inflation pressure

Information for your safety

The factory-approved tires are matched
to your vehicle and have been selected
to provide optimum safety and driving
comfort when used properly.

It is not merely the tire's service life, but
also driving comfort and – above all else
– driving safety that depend on the con-
dition of the tires and the maintenance
of the specified tire inflation pressure.

Incorrect tire inflation pressure is a fre-
quent cause of tire damage. Tire pres-
sure also has a major effect on your
BMW's handling response.

Be sure to check the tire inflation
pressure, including the pressure

of the space-saver spare tire or the
spare tire, on a regular basis, at least
twice a month and before every
extended journey, refer to page

Otherwise, incorrect tire pressure can
lead to poor handling, to tire damage
and accidents.

Tire condition

Tire tread – tire damage

Inspect your tires frequently for tread
wear, signs of damage and for foreign
objects lodged in the tread. Check the
tread depth.

Tread depth should not be allowed to
go below 1/8 in / 3 mm, even though
the legally specified minimum tread
depth is 1/16 in / 1.6 mm.

Below 1/8 in / 3 mm tread depth, there
is a great risk of hydroplaning, even at
relatively moderate speeds and with
only small amounts of water on the
road. Tread wear indicators in the
tread-groove base – see arrow – are
distributed around the wheel circumfer-
ence and are labeled on the tire side-

wall with TWI – Tread Wear Indicator. At
a tread depth of 1/16 in / 1.6 mm, the
indicators signal that the legally permis-
sible wear limit has been reached.

Do not drive on a deflated – flat –
tire. A flat tire greatly impairs

steering and braking response, and can
lead to complete loss of control over
the vehicle. Avoid overloading the vehi-
cle so that the permitted load on the
tires is not exceeded. Overloading can
lead to overheating and internal tire
damage.
The ultimate result can assume the
form of a sudden air loss.
Unusual vibrations encountered during
normal vehicle operation can indicate a
flat tire or some other vehicle malfunc-
tion. This type of problem can be
caused by contact with curbs, etc. This
is also true for irregularities in the vehi-
cle's handling characteristics, such as a
pronounced tendency to pull to the left
or right. Should this occur, respond by
immediately reducing your speed. Pro-

Overview

Controls

Maintenance

Repairs

Data

Index