To avoid hazardous situations:
Rnever install snow chains to the front
wheels
Ralways install snow chains in pairs to the
rear wheels.
!You must drive at raised vehicle level (height
1) if snow chains have been installed. The
vehicle may otherwise be damaged.
!Vehicles with ADS (Adaptive Damping
System): do not use the sport mode when
driving with snow chains mounted. The vehi-
cle may otherwise be damaged.
For safety reasons, Mercedes-Benz recom-
mends that you only use snow chains that have
been specially approved for your vehicle by
Mercedes-Benz, or are of a corresponding
standard of quality. For more information,
please contact a qualified specialist workshop.
Install the snow chains on all driven wheels for
maximum tractive power and driving stability. If
you own snow chains for two driven wheels only,
install the snow chains to the wheels on the rear
axle. The vehicle then remains more stable
under braking.
If you intend to mount snow chains, please bear
the following points in mind:
RSnow chains may not be mounted on all
wheel/tire combinations. Permissible
wheel/tire combinations (
Ypage 345).
ROnly use snow chains when driving on roads
completely covered by snow. Remove the
snow chains as soon as possible when you
come to a road that is not snow-covered.
RLocal regulations may restrict the use of snow chains. Observe the appropriate regulations if
you wish to mount snow chains.
RDo not exceed the maximum permissible
speed of 30 mph (50 km/h).
RNever use Parking Pilot when snow chains are
installed (Ypage 177).
You may wish to deactivate ESP®when pulling
away with snow chains installed (Ypage 65).
You can thereby allow the wheels to spin in a
controlled manner, achieving an increased driv-
ing force (cutting action).
Information about driving with an emergency
spare wheel (
Ypage 346).
Tire pressure
Tire pressure specifications
Important safety notes
GWARNING
Underinflated or overinflated tires pose the
following risks:
Rthe tires may burst, especially as the load
and vehicle speed increase.
Rthe tires may wear excessively and/or
unevenly, which may greatly impair tire
traction.
Rthe driving characteristics, as well as steer-
ing and braking, may be greatly impaired.
There is a risk of an accident.
Follow recommended tire inflation pressures
and check the pressure of all the tires includ-
ing the spare wheel:
Rmonthly, at least
Rif the load changes
Rbefore beginning a long journey
Runder different operating conditions, e.g.
off-road driving
If necessary, correct the tire pressure.
The data on the Tire and Loading Information
placard and tire pressure table shown here are
examples. Tire pressure specifications are vehi-
cle-specific and may deviate from the data
shown here. The tire pressure specifications
that are valid for your vehicle can be found on
the Tire and Loading Information placard and
tire pressure table on the vehicle.
General notes
The recommended tire pressures for the tires
mounted at the factory can be found on the
labels described here.
Operation with emergency spare wheel:
Information on operation with the emergency
spare wheel can be found under "Emergency
spare wheel" (
Ypage 346).
Operation with a trailer: the applicable value
for the rear axle is the maximum tire pressure
value stated in the table inside the fuel filler flap.
324Tire pressure
Wheels and tires
Vehicle identification plate
Even if you have calculated the total cargo care-
fully, you should still make sure that the gross
vehicle weight rating and the gross axle weight
rating are not exceeded. Details can be found on
the vehicle identification plate on the B-pillar on
the driver's side of the vehicle (
Ypage 331).
Permissible Gross Vehicle Weight Rating
(GVWR): the gross weight of the vehicle, all pas-
sengers, load and trailer load/noseweight (if
applicable) must not exceed the permissible
gross vehicle weight.
Gross Axle Weight Rating (GAWR): the maxi-
mum permissible weight that can be carried by
one axle (front or rear axle).
To ensure that your vehicle does not exceed the
maximum permissible values (gross vehicle
weight and maximum gross axle weight rating),
have your loaded vehicle (including driver, occu-
pants, cargo, and full trailer load if applicable)
weighed on a suitable vehicle weighbridge.
Trailer load/noseweight
The trailer load/noseweight affects the gross
weight of the vehicle. If a trailer is attached, the trailer load/noseweight is included in the load
along with occupants and luggage. The trailer
load/noseweight is usually approximately 8% of
the gross weight of the trailer and its cargo.
All about wheels and tires
Uniform Tire Quality Grading Stand-
ards
Overview of Tire Quality Grading Stand-
ards
Uniform Tire Quality Grading Standards are U.S.
government specifications. Their purpose is to
provide drivers with uniform reliable information
on tire performance data. Tire manufacturers
have to grade tires using three performance fac- tors: :tread wear grade, ;traction grade and
= temperature grade. These regulations do not
apply to Canada. Nevertheless, all tires sold in
North America are provided with the corre-
sponding quality grading markings on the side-
wall of the tire.
Quality grades can be found, where applicable,
on the tire sidewall between tread shoulder and
maximum section width.
Example:
RTreadwear grade: 200
RTraction grade:AA
RTemperature grade: A
All passenger car tires must conform to the stat-
utory safety requirements in addition to these
grades.
iThe actual values for tires are vehicle-spe-
cific and may deviate from the values in the
illustration.
Treadwear
The treadwear grade is a comparative rating
based on the wear rate of the tire when tested
under controlled conditions on a specified U.S.
government course. For example, a tire graded
150 would wear one and one-half times as well
on the government course as a tire graded 100.
The relative performance of tires depends upon the actual conditions of their use, however, and
may depart significantly from the norm due to
variations in driving habits, service practices
and differences in road characteristics and cli-
mate.
Traction
GWARNING
The traction grade assigned to this tire is
based on straight-ahead braking traction
tests, and does not include acceleration, cor-
nering, hydroplaning, or peak traction char-
acteristics.
!Avoid wheelspin. This can lead to damage to
the drive train.
334All about wheels and tires
Wheels and tires
The traction grades – from highest to lowest –
are AA, A, B and C. Those grades represent the
tire's ability to stop on wet pavement as meas-
ured under controlled conditions on specified
government test surfaces of asphalt and con-
crete. A tire marked C may have poor traction
performance.
The safe speed on a wet, snow covered or icy
road is always lower than on dry road surfaces.
You should pay special attention to road condi-
tions when temperatures are around freezing
point.
Mercedes-Benz recommends a minimum tread
depth ofãin (4 mm) on all four winter tires.
Observe the legally required minimum tire tread
depth (
Ypage 322). Winter tires can reduce the
braking distance on snow-covered surfaces in
comparison with summer tires. The braking dis-
tance is still much further than on surfaces that are not icy or covered with snow. Take appro-
priate care when driving.
Further information on winter tires (M+S tires)
(
Ypage 323).
Temperature
GWARNING
The temperature grade for this tire is estab-
lished for a tire that is properly inflated and
not overloaded. Excessive speed, underinfla-
tion, or excessive loading, either separately or
in combination, can cause excessive heat
build-up and possible tire failure.
The temperature grades are A (the highest), B,
and C, representing the tire's resistance to the
generation of heat and its ability to dissipate
heat when tested under controlled conditions
on a specified indoor laboratory test wheel. Sus-
tained high temperature can cause the material
of the tire to degenerate and reduce tire life, and
excessive temperature can lead to sudden tire
failure. The grade C corresponds to a level of
performance which all passenger car tires must
meet under the Federal Motor Vehicle Safety
Standard No. 109. Grades B and A represent
higher levels of performance on the laboratory
test wheel than the minimum required by law.
Tire labeling
Overview
:Uniform Tire Quality Grading Standards
(Ypage 339)
;Department of Transportation, Tire Identifi-
cation Number (Ypage 338)
=Maximum load rating (Ypage 338)
?Maximum tire pressures (Ypage 327)
AManufacturer
BTire material (Ypage 338)
CTire size designation, load-bearing capacity
and speed rating (Ypage 335)
DLoad index (Ypage 337)
ETire name
The markings described above are on the tire in
addition to the tire name (sales designation) and
the manufacturer's name.
iTire data is vehicle-specific and may deviate
from the data in the example.
Tire size designation, load-bearing
capacity and speed rating
GWARNING
Exceeding the stated tire load-bearing capa-
city and the approved maximum speed could
lead to tire damage or the tire bursting. There is a risk of accident.
Therefore, only use tire types and sizes
approved for your vehicle model. Observe the
All about wheels and tires335
Wheels and tires
Z
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.
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 out-
ward force to each square inch of the tire's sur-
face. The tire pressure is specified in pounds per
square inch (psi), in kilopascal (kPa) or in bar.
The tire pressure should only be corrected whenthe tires are cold.
Cold tire pressure
The tires are cold:
Rif the vehicle has been parked with the tires
out of direct sunlight for at least three hours
and
Rif 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-per-
formance battery, are not included in the curb
weight and the weight of the accessories.
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 pur-
chasers. The TIN is made up of the manufactur- er's identity code, tire size, tire type code and
the manufacturing date.
Load bearing index
The load bearing index (also load index) is a code
that contains the maximum load bearing capa-
city 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.
Treadwear indicators
Narrow bars (tread wear bars) that are distrib-
uted over the tire tread. If the tire tread is level
with the bars, the wear limit of áin (1.6 mm)
has been reached.
Occupant distribution
The distribution of occupants in a vehicle at their
designated seating positions.
Total load limit
Nominal load and luggage load plus 68 kg
(150 lbs) multiplied by the number of seats in
the vehicle.
340All about wheels an d tires
Wheels and tires