Important notes on tire pressure
G WARNIN G
If th e tire pressur e drops repeatedly, th e
wheel, valv e or tire may be damaged. Tir e
pressur e that is to o low may result in a tire
blow-out . Ther e is a ris k of an accident.R
Chec k th e tire for foreign objects .R
Chec k whether th e whee l is losing air or th e
valv e is leaking .
If you are unable to rectify th e damage, con-
tac t a qualified specialist workshop.
G WARNIN G
If you fit unsuitable accessories onto tire
valves, th e tire valves may be overloaded and
malfunction , whic h can caus e tire pressur e
loss . Due to their design , retrofitte d tire pres-
sur e monitors keep th e tire valv e open . This
can also result in tire pressur e loss . Ther e is a
ris k of an accident.
Only screw th e standard valv e cap or other
valv e cap s approve d by Mercedes-Ben z for
your vehicl e onto th e tire valve.
Use a suitable pressur e gauge to chec k th e tire
pressure. The outer appearanc e of a tire does
no t permit any reliable conclusio n about th e tire
pressure. On vehicles equipped wit h th e elec -
tronic tire pressur e monitor, th e tire pressur e
can be checke d in th e on-board computer.
The tire temperature and pressur e increas e
when th e vehicl e is in motion . This is dependen t
on th e driving spee d and th e load.
Therefore, you should only correc t tire pres-
sures when th e tires are cold.
The tires are cold: R
if th e vehicl e has been parked wit h th e tires
out of direct sunligh t for at least three hour s
and R
if th e vehicl e has been driven less than 1 mile
(1.6 km )
Th e tire temper ature changes depending on the
outside temperature, the vehicle speed and the
tire load. If t he tire temperature changes by
1
8 ‡ (10 †), the tire pressure changes by
approximately 10 kPa (0.1 bar/1.5 psi). Take
this into account when checking the pressure of
warm tires. Only correct the tire pressure if it is too low for the current operating conditions. If
you check the tire pressure when the tires are
warm, the resulting value will be higher than if
the tires were cold. This is normal. Do not
reduce the tire pressure to the value specified
for cold tires. The tire pressure would otherwise
be too low.
Observe the recommended tire pressures for
cold tires: R
on the Tire and Loading Information placard
on the B-pillar on the driver's side R
in the tire pressure table in the fuel filler flap
( Y
page 138)
Underinflated or overinflated tires
Underinflated tires
G WARNING
Tires with pressure that is too low can over-
heat and burst as a consequence. In addition,
they also suffer from excessive and/or irreg-
ular wear, which can severely impair the brak-
ing properties and the driving characteristics.
There is a risk of an accident.
Avoid tire pressures that are too low in all the
tires, including the spare wheel.
Underinflated tires may: R
overheat, leading to tire defects R
adversely affect handling R
wear excessively and/or unevenly R
have an adverse effect on fuel consumption
Overinflated tires
G WARNING
Tires with excessively high pressure can burst
because they are damaged more easily by
road debris, potholes etc. In addition, they
also suffer from irregular wear, which can
severely impair the braking properties and the
driving characteristics. There is a risk of an
accident.
Avoid tire pressures that are too high in all the
tires, including the spare wheel. Tire pressure 287
Wheels and tires Z
Uniform Tire Quality Grading Standards A uniform standard to grade the quality of tires
with regards to tread quality, tire traction and
temperature characteristics. The quality grad-
ing assessment is made by the manufacturer
following specifications from the U.S. govern-
ment. The ratings are molded into the sidewall of
the tire.
Recommended tire pressures The recommended tire pressure applies to the
tires mounted at the factory.
The Tire and Loading Information placard con-
tains the recommended tire pressures for cold
tires on a fully loaded vehicle and for the maxi-
mum permissible vehicle speed.
The tire pressure table contains the recommen-
ded pressures for cold tires for various operat-
ing conditions, i.e. differing load and speed con-
ditions.
Increased vehicle weight due to optional
equipment The combined weight of all standard and
optional equipment available for the vehicle,
regardless of whether it is actually installed on
the vehicle or not.
Rim This is the part of the wheel on which the tire is
mounted.
GAWR (Gross Axle Weight Rating) The GAWR is the maximum gross axle weight
rating. The actual load on an axle must never
exceed the gross axle weight rating. The gross
axle weight rating can be found on the vehicle
identification plate on the B-pillar on the driver's
side.
Speed rating
The speed rating is part of the tire identification.
It specifies the speed range for which the tire is
approved.
GVW (Gross Vehicle Weight)
The gross vehicle weight includes the weight of
the vehicle including fuel, tools, the spare wheel,
accessories installed, occupants, luggage and
the drawbar noseweight, if applicable. The gross
vehicle weight must not exceed the gross vehi-
cle weight rating GVWR as specified on the vehi-
cle identification plate on the B-pillar on the
driver's side. GVWR (Gross Vehicle Weight Rating) The GVWR is the maximum permissible gross
weight of a fully loaded vehicle (the weight of the
vehicle including all accessories, occupants,
fuel, luggage and the drawbar n oseweight, if
applicable). The gross vehicle weight rating is
specified on the vehicle identification plate on
the B-pillar on the driver's side.
Maximum loaded vehicle weight The maximum weight is the sum of: R
the curb weight of the vehicle R
the weight of the accessories R
the load limit R
the weight of the factory installed optional
equipment
Kilopascal (kPa) Metric unit for tire pressure. 6.9 kPa corre-
sponds to 1 psi. Another unit for tire pressure is
bar. 100 kilopascals (kPa) are the equivalent of
1 bar.
Load index In addition to the load-bearing index, the load
index may also be imprinted on the sidewall of
the tire. This specifies the load-bearing capacity
more precisely.
Curb weight The weight of a vehicle with standard equipment
including the maximum capacity of fuel, oil and
coolant. It also includes the air-conditioning sys-
tem and optional equipment if these are instal-
led in the vehicle, but does not include passen-
gers or luggage.
Maximum load rating
The maximum tire load is the maximum permis-
sible 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.300
All about wheels and tires
Wheels and tires
