the tire. This specifies the load-bearing capa-
city more precisely.
Curb weight
The weight of a vehicle with standard equip-
ment including the maximum capacity of fuel,
oil and coolant. It also includes the air-condi-
tioning system and optional equipment if
these are installed in the vehicle, but does not
include passengers or luggage.
Maximum load rating
The maximum load rating is the maximum
permissible weight in kilograms or lbs for
which a tire is approved.
Maximum permissible tire pressure
Maximum permissible tire pressure for one
tire.
Maximum load on one tire
Maximum load on one tire. This is calculated
by dividing the maximum axle load of one axle
by two.
PSI (pounds per square inch)
A standard unit of measure for tire pressure.
Aspect ratio
Relationship between tire height and tire
width in percent.
Tire pressure
This is pressure inside the tire applying an
outward force to each square inch of the tire's
surface. The tire pressure is specified in
pounds per square inch (psi), in kilopascal
(kPa) or in bar. The tire pressure should only
be corrected when the tires are cold.
Cold tire pressure
The tires are cold: R
if the vehicle has been parked without
direct sunlight on the tires for at least three
hours and R
if the vehicle has not been driven further
than 1 mile (1.6 km) Tread
The part of the tire that comes into contact
with the road.
Bead
The tire bead ensures that the tire sits
securely on the wheel. There are several steel
wires in the bead to prevent the tire from
coming loose from the wheel rim.
Sidewall
The part of the tire between the tread and the
bead.
Weight of optional extras
The combined weight of those optional extras
that weigh more than the replaced standard
parts and more than 2.3 kg (5 lbs). These
optional extras, such as high-performance
brakes, level control, a roof rack or a high-
performance battery, are not included in the
curb weight and the weight of the accesso-
ries.
TIN (Tire Identification Number)
This is a unique identifier which can be used
by a tire manufacturer to identify tires, for
example for a product recall, and thus identify
the purchasers. The TIN is made up of the
manufacturer's identity code, tire size, tire
type code and the manufactu ring date.
L o ad bearing index
The load bearing index (also load index) is a
code that contains the maximum load bearing
capacity of a tire.
Traction
Traction is the result of friction between the
tires and the road surface.
TWR (Tongue Weight Rating)
The TWR specifies the maximum permissible
weight that the ball coupling of the trailer tow
hitch can support.426
All about wheels an d tires
Wheels and tires
The recommended pressures for various
operating conditions can be found: R
on the Tire and Loading Information placard
with the recommended tire pressures on
the B-pillar on the driver's side R
in the tire pressure table on the inside of the
fuel filler flap
Observe the notes on recommended tire
pressures under various operating conditions
( Y
page 408).
Check tire pressures regularly, and only when
the tires are cold. Comply with the mainte-
nance recommendations of the tire manufac-
turer in the vehicle document wallet.
Notes on the vehicle equipment – always
equip the vehicle with: R
tires of the same size across an axle (left
and right) R
the same type of tires at a given time (sum-
mer tires, winter tires, MOExtended tires)
Vehicles equipped with MOExtended tires are
not equipped with a TIREFIT kit at the factory.
It is therefore recommended that you addi-
tionally equip your vehicle with a TIREFIT kit if
you mount tires that do not feature run-flat
properties, e.g. winter tires. A TIREFIT kit may
be obtained from a qualified specialist work-
shop.
i Not all wheel and tire combinations are
available at the factory for all countries.
i The following pages contain information
on approved wheel rims and tire sizes for
equipping your vehicle with winter tires.
Winter tires are not available at the factory
as standard equipment or optional extras.
If you want to equip your vehicle with
approved winter tires, it may be necessary
to obtain wheel rims in the corresponding
size. The size of the approved winter tires
may differ from the standard tires. This is
dependent on the model and the equip-
ment installed at the factory.
The tires and wheel rims, as well as further
information, can be obtained at a qualified
specialist workshop. Wheel and tire combinations 433
Wheels and tires Z
