2017 MERCEDES-BENZ CLA-Class traction control

with run-flat characteristics)" section
(Ypage 267).
ROnly mount tires of the correct size onto the
wheels.
RBreak in new tires at moderate speeds for the
first 60 miles(100km). Th ene w tires only
reach their full performance after this dis-
tance.
RDo not drive with tires which have too little
tread depth, as this significantly reduces the
traction on wet roads (hydroplaning).
RReplace the tires after six years at the latest,
regardless of wear.
MOExtended tires (tires with run-flat
properties)
With MOExtended tires (tires with run flat char-
acteristics), you can continue to drive your vehi-
cle even if there is a total loss of pressure in one
or more tires.
MOExtended tires may only be used in conjunc-
tion with an activated tire pressure loss warning
system (Canada only) or tire pressure monitor
(USA only) and only on wheels specifically tes-
ted by Mercedes-Benz.
Notes on driving with MOExtended tires with a
flat tire (
Ypage 267).
Vehicles equipped with MOExtended tires are
not equipped with a TIREFIT kit at the factory. It
is therefore recommended that you additionally
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 workshop.
Winter operation
General notes
Have your vehicle winter-proofed at a qualified
specialist workshop at the onset of winter.
Observe the notes in the "Changing a wheel"
section (
Ypage 301).
Driving with summer tires
At temperatures below 45 ‡ (+7 †), summer
tires lose elasticity and therefore traction and
braking power. Change the tires on your vehicle
to M+S tires. Using summer tires at very cold temperatures could cause cracks to form,
thereby damaging the tires permanently.
Mercedes-Benz cannot accept responsibility for
this type of damage.
GWARNING
Damaged tires can cause tire inflation pres-
sure loss. As a result, you could lose control of
your vehicle. There is a risk of accident.
Check the tires regularly for signs of damage
and replace any damaged tires immediately.
M+S tires
GWARNING
M+S tires with a tire tread depth of less than
ã in(4 mm ) are not suitable for use in winter
and do not provide sufficient traction. There is
a risk of an accident.
M+S tires with a tread depth of less than ãin
(4 mm) must be replaced immediately.
At temperatures below 45 ‡(+7 †), use winter
tires or all-season tires. Both types of tire are
identified by the M+S marking.
Only winter tires bearing the isnowflake
symbol in addition to the M+S marking provide
the best possible grip in wintry road conditions.
Only these tires will allow driving safety systems
such as ABS and ESP
®to function optimally in
winter. These tires have been developed specif-
ically for driving in snow.
Use M+S tires of the same make and tread on all
wheels to maintain safe handling characteris-
tics.
Always observe the maximum permissible
speed specified for the M+S tires you have
mounted.
When you have mounted the M+S tires:
XCheck the tire pressures (Ypage 285).
XRestart the tire pressure monitor (USA only)
(Ypage 291).
XRestart the tire pressure loss warning system
(Canada) (Ypage 289)
284Winter operation
Wheels and tires

Snow chains
GWARNING
If snow chains are mounted on the rear
wheels, the snow chains could cause abrasion
to the vehicle body or to chassis components.
This could cause damage to the vehicle or the
tires. There is a risk of an accident.
To avoid hazardous situations:
Rnever mount snow chains on the rear
wheels
Ronly mount snow chains in pairs on the
front wheels.
!On some tire sizes there is not enough space
for snow chains. To avoid damage to the vehi-
cle or tires, observe the "Wheel and tire com-
binations" section under "Tires and wheels".
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.
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 306).
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).
RDo not use Parking Pilot when snow chains
are installed (Ypage 162).
You may wish to deactivate ESP®(Ypage 63)
when pulling away with snow chains installed .
You can thereby allow the wheels to spin in a
controlled manner, achieving an increased driv-
ing force (cutting action).
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.
iThe data on the Tire and Loading Informa-
tion placard and tire pressure table shown
here are examples. Tire pressure specifica-
tions are vehicle-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 Infor-
mation 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.
Further information on tire pressures can be
obtained at a qualified specialist workshop.
Tire pressure285
Wheels and tires
Z

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.
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.
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 of ãin (4 mm) on all four winter tires.
All about wheels and tires295
Wheels and tires
Z

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 when
the 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 fromthe 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.
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.
Changing a wheel
Flat tire
The "Breakdown assistance" section
(Ypage 266) contains information and notes on
how to deal with a flat tire. Information on driv-
ing with MOExtended tires in the event of a flat
tire can be found under "MOExtended tires (tires
with run-flat characteristics" (
Ypage 267).
Rotating the wheels
GWARNING
Interchanging the front and rear wheels may
severely impair the driving characteristics if
the wheels or tires have different dimensions. The wheel brakes or suspension components
may also be damaged. There is a risk of acci-
dent.
Rotate front and rear wheels only if the wheels and tires are of the same dimensions.
!On vehicles equipped with a tire pressure
monitor, electronic components are located
in the wheel.
Changing a wheel301
Wheels and tires
Z