tires MERCEDES-BENZ B-CLASS 2012 Owner's Manual

The maximum driving distance is
approximately 50 miles (80 km) when the
vehicle is partially laden and approximately
18 miles (30 km) when the vehicle is fully
laden.
In addition to the vehicle load, the driving
distance possible depends upon:
R Speed
R Road condition
R Outside temperature
The driving
distance possible in run-flat mode
may be reduced by extreme driving
conditions/maneuvers, or it can be increased
through a moderate style of driving.
The maximum permissible distance which
can be driven in run-flat mode is counted from
the moment the tire pressure loss warning
appears in the multifunction display.
You must not exceed a maximum speed of
50 mph (80 km/h).
i When replacing one or all tires, make sure
that you use only tires:
R of the size specified for the vehicle and
R marked "MOExtended"
If a tire has gone flat and cannot be
replaced with a MOExtended tire, a
standard tire may be used as a temporary
measure. Make sure that you use the
proper size and type (summer or winter
tire).
i 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 can be obtained from a
qualified specialist workshop.
Important safety notes G
WARNING
When driving in emergency mode, the driving
characteristics deteriorate, e.g. when cornering, accelerating quickly and when
braking. There is a risk of an accident.
Do not exceed the stated maximum speed.
Avoid abrupt
steering
and driving maneuvers,
and driving over obstacles (curbs, potholes,
off-road). This applies in particular to a laden
vehicle.
Stop driving in emergency mode if:
R you hear banging noises.
R the vehicle starts to shake.
R you see smoke and smell rubber.
R ESP ®
is intervening constantly.
R there are tears in the sidewalls of the tire.
After driving in emergency mode, have the
wheel rims checked at a qualified specialist
workshop with regard to their further use. The
defective tire must be replaced in every case. TIREFIT kit
Important safety notes G
WARNING
In the following situations, the tire sealant is
unable to provide sufficient breakdown
assistance, as it is unable to seal the tire
properly:
R there are cuts

or punctures in the tire larger
than those mentioned above.
R the wheel rim is damaged.
R you have driven at very low tire pressures
or on a flat tire.
There is a risk of an accident.
Do not drive any further. Contact a qualified
specialist workshop. G
WARNING
The tire sealant is harmful and causes
irritation. It must not come into contact with
your skin, eyes or clothing or be swallowed.
Do not inhale

TIREFIT fumes. Keep tire sealant
away from children. There is a risk of injury. 282
Flat tire
Breakdown assistance
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X
Press on/off switch ? on the tire inflation
compressor to ON.
The tire inflation compressor is switched
on. The tire is inflated.
i First, tire sealant is pumped into the tire.
The pressure can briefly rise to
approximately 500 kPa (5 bar/73 psi).
Do not switch off the tire inflation
compressor during this phase.
X Let the tire inflation compressor run for a
maximum of ten minutes. The tire should
then have attained a pressure of at least
200 kPa (2.0 bar/29 psi).
! Do not operate the tire inflation
compressor for longer than ten minutes at
a time without a break. It may otherwise
overheat.
The tire inflation compressor can be
operated again once it has cooled down.
If a pressure

of 200 kPa (2.0 bar/29 psi) has
been attained after a maximum of after ten
minutes, see ( Y page 284).
If a pressure of 200 kPa (2.0 bar/29 psi) has
not been attained after a maximum of ten
minutes, see ( Y page 284).
i If tire sealant leaks out, allow it to dry. It
can then be removed like a layer of film.
If your clothes are soiled with tire sealant,
have them cleaned with perchloroethylene
at a dry cleaner as soon as possible.
Tire pressure not reached If a pressure of 200 kPa (
2.0 bar
/29 psi) has
not been achieved after ten minutes:
X Switch off the tire inflation compressor.
X Unscrew the filler hose from the valve of
the faulty tire.
X Very slowly drive forwards or reverse
approximately 30 ft (10 m).
X Pump up the tire again.
After a maximum of ten minutes, the tire
pressure

must be
at least 200 kPa (2.0 bar/
29 psi). G
WARNING
If the required tire pressure is not reached
after the specified time, the tire is too badly
damaged. The tire sealant cannot repair the
tire in this

instance. Damaged tires and a tire
pressure that is too low can significantly
impair the vehicle's braking and driving
characteristics. There is a risk of accident.
Do not continue driving. Contact a qualified
specialist workshop.
Tire pressure reached G
WARNING
A tire temporarily sealed with tire sealant
impairs the driving characteristics and is not
suitable for higher speeds. There is a risk of
accident.
You should therefore adapt your driving style
accordingly and drive

carefully. Do not exceed
the specified maximum speed with a tire that
has been repaired using tire sealant.
! After use, excess tire sealant may run out
of the filler hose. This could cause stains.
Therefore, place the filler hose in the plastic
bag that contained the TIREFIT kit. H
Environmental note
Have the used tire sealant bottle disposed of
professionally, e.g. at a qualified specialist
workshop.
If a tire

pressure of 200 kPa (2.0 bar/29 psi)
has been achieved after ten minutes:
X Switch off the tire inflation compressor.
X Unscrew the filler hose from the valve of
the faulty tire.
X Stow the tire sealant bottle and the tire
inflation compressor.
X Pull away immediately.
The maximum speed for a tire sealed with tire
sealant is 50 mph (

80 km/h). The upper part
of the TIREFIT sticker must be affixed to the
instrument cluster in the driver's field of
vision. 284
Flat tire
Breakdown assistance
ProCarManuals.com

X
Stop after driving for approximately ten
minutes and check the tire pressure with
the tire inflation compressor.
The tire pressure must now be at least
130 kPa (1.3 bar/19 psi). G
WARNING
If the required tire pressure is not reached
after driving for a short period, the tire is too
badly damaged. The
tire sealant cannot repair
the tire in this instance. Damaged tires and a
tire pressure that is too low can significantly
impair the vehicle's braking and driving
characteristics. There is a risk of accident.
Do not continue driving. Contact a qualified
specialist workshop.
X Correct the tire pressure if it is still at least
130 kPa (1.3 bar/19 psi) (for the values,
see the Tire and Loading Information
placard on the driver's side B-pillar or tire
pressure table on the fuel filler flap).
X To increase the tire pressure: switch on
the tire inflation compressor. X
To reduce the tire pressure: depress
pressure release button : next to
pressure gauge ;. X
To remove the tire sealant bottle from the
tire inflation compressor, press together
the locking tabs on the yellow cap.
X Pull the tire sealant bottle out of the tire
inflation compressor.
The filler hose

remains attached to the tire
sealant bottle.
X Stow the tire sealant bottle and the tire
inflation compressor.
X Drive to the nearest qualified specialist
workshop and have

the tire changed there.
X Have the tire sealant bottle and the filler
hose replaced as soon as possible at a
qualified specialist workshop.
X Have the tire sealant bottle replaced every
four years at a qualified specialist
workshop. Battery (vehicle)
Important safety notes
Special tools and expert knowledge are
required when working on the battery, e.g.
removal and installing. You should therefore
have all work

involving the battery carried out
at a qualified specialist workshop. G
WARNING
Work carried out incorrectly on the battery
can, for example, lead to a short circuit and
damage your vehicle's

electronic system. This
can disrupt driving safety systems such as
ABS (anti-lock braking system) or ESP ®
(Electronic Stability Program). Battery (vehicle)
285
Breakdown assistance
ZProCarManuals.com

Useful information ............................
298
Important safety notes ....................298
Operation ........................................... 298
Winter operation ............................... 300
Tire pressure ..................................... 301
Loading the vehicle ..........................306
Maximum load rating .......................310
Uniform Tire Quality Grading
Standards .......................................... 311
Tire labeling ....................................... 312
Definition of terms for tires and
loading ............................................... 316
Changing a wheel ............................. 319
Wheel and tire combinations ...........323
Emergency spare wheel ...................325 297Wheels and tires
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Useful information
i This Operator's Manual describes all
models and all standard and optional
equipment of your vehicle available at the
time of publication of the Operator's
Manual. Country-specific differences are
possible. Please note
that your vehicle may
not be equipped with all features
described. This also applies to safety-
related systems and functions.
i Read the information on qualified
specialist workshops: ( Y page 24).Important safety notes
G
WARNING
If wheels and tires of the wrong size are used,
the wheel brakes or suspension components
may be damaged. There is a risk of an
accident.
Always replace wheels and tires with those
that fulfill the specifications of the original
part.
When replacing wheels,

make sure to use the
correct:
R designation
R model
When replacing tires, make sure to use the
correct:
R designation
R manufacturer
R model G
WARNING
A flat tire severely impairs the driving,
steering and braking characteristics of the
vehicle. There is a risk of accident.
Tires without run-flat characteristics:
R do not drive with a flat tire.
R immediately replace the flat tire with your
emergency spare wheel or spare wheel, or
consult a qualified specialist workshop. Tires with run-flat characteristics:
R
pay attention to the information and
warning notices on

MOExtended tires (tires
with run-flat characteristics).
Accessories that are not approved for your
vehicle by Mercedes-Benz or are not being
used correctly can impair the operating
safety.
Before purchasing and using non-approved
accessories, visit a qualified specialist
workshop and inquire about:
R suitability
R legal stipulations
R factory recommendations
Information on dimensions and types of
wheels and tires for your vehicle can be found
(Y page 323).
Information on air pressure for the tires on
your vehicle can be found:
R on the vehicle's Tire and Loading
Information placard on the B-pillar
R on the tire pressure label on the fuel filler
flap
R under "Tire pressure"
i Further information on wheels and tires
can be obtained at any qualified specialist
workshop. Operation
Information on driving
R If the vehicle is heavily loaded, check the
tire pressures and correct them if
necessary.
R While driving, pay attention to vibrations,
noises and unusual handling
characteristics, e.g. pulling to one side.
This may indicate that the wheels or tires
are damaged. If you suspect that a tire is
defective, reduce your speed immediately.
Stop the vehicle as soon as possible to
check the wheels and tires for damage.
Hidden tire damage could also be causing298
Operation
Wheels and tires
ProCarManuals.com

the unusual handling characteristics. If you
find no signs of damage, have the wheels
and tires checked at a qualified specialist
workshop.
R When parking your
vehicle, make sure that
the tires do not get deformed by the curb
or other obstacles. If it is necessary to drive
over curbs, speed humps or similar
elevations, try to do so slowly and at an
obtuse angle. Otherwise, the tires,
particularly the sidewalls, may be
damaged. Regular checking of wheels and tires
G
WARNING
Damaged tires can cause tire inflation
pressure 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.
Regularly check the wheels and tires of your
vehicle for damage

at least once a month, as
well as after driving off-road or on rough
roads. Damaged wheels can cause a loss of
tire pressure. Pay particular attention to
damage such as:
R cuts in the tires
R punctures
R tears in the tires
R bulges on tires
R deformation or severe corrosion on wheels
Regularly check the tire tread depth and the
condition of the tread across the whole width
of the tire (Y page 299). If necessary, turn
the front wheels to full lock in order to inspect
the inner side of the tire surface.
All wheels must have a valve cap to protect
the valve against dirt and moisture. Do not
mount anything onto the valve other than the
standard valve cap or other valve caps
approved by Mercedes-Benz for your vehicle. Do not use any other valve caps or systems,
e.g. tire pressure monitoring systems.
Regularly check the pressure of all the tires
particularly prior
to

long trips. Adjust the tire
pressure as necessary ( Y page 301).
The service life of tires depends, among other
things, on the following factors:
R Driving style
R Tire pressure
R Distance covered Tire tread
G
WARNING
Insufficient tire tread will reduce tire traction.
The tire is no longer able to dissipate water.
This means that

on wet road surfaces, the risk
of hydroplaning increases, in particular where
speed is not adapted to suit the driving
conditions. There is a risk of accident.
If the tire pressure is too high or too low, tires
may exhibit different levels of wear at
different locations on the tire tread. Thus, you
should regularly check the tread depth and
the condition of the tread across the entire
width of all tires.
Minimum tire tread depth for:
R Summer tires: â in (3 mm)
R M+S tires: ã in (4 mm)
For safety reasons, replace the tires before
the legally prescribed limit for the minimum
tire tread depth is reached. Operation
299
Wheels and tires Z
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Bar indicator : for tread wear is integrated
into the tire tread.
Treadwear indicators (TWI) are required by
law. Six indicators are positioned on the tire
tread. They are visible once the tread depth
is approximately
á
in (1.6 mm). If this is the
case, the tire is so worn that it must be
replaced. Selecting, mounting and replacing
tires
R Only mount tires and wheels of the same
type and make.
Exception: it is permissible to mount a
different type or

make in the event of a flat
tire. Observe the "MOExtended tires (tires
with run-flat characteristics" section
(Y page 281).
R Only mount tires of the correct size onto
the wheels.
R After mounting new tires, break in them in
at moderate speeds for the first 60 miles
(100 km), as they only reach their full
performance after this distance.
R Do not drive with tires which have too little
tread depth, as this significantly reduces
the traction on wet roads (hydroplaning).
R Replace 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
characteristics), you can continue to drive
your vehicle even if there is a total loss of
pressure in one or more tires.
MOExtended tires may only be used in
conjunction with an active tire pressure loss
warning system and only on wheels
specifically tested by Mercedes-Benz.
Notes on driving with MOExtended tires with
a flat tire ( Y page 281). i
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 can be obtained from a
qualified specialist workshop. Winter operation
General notes
Have your vehicle

winterproofed at a qualified
specialist workshop at the onset of winter.
Observe the notes in the "Changing a wheel"
section ( Y page 319). 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. M+S tires
G
WARNING
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 ã
in (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 i snowflake
symbol in addition to the M+S marking
provide the best possible grip in wintry road
conditions. Only these tires will allow driving 300
Winter operation
Wheels and tires
ProCarManuals.com

safety systems such as ABS and ESP
®
to
function optimally in
winter. These tires have
been developed specifically for driving in
snow.
Use M+S tires of the same make and tread on
all wheels to maintain safe handling
characteristics.
Always observe the maximum permissible
speed specified for the M+S tires you have
mounted.
Once the winter tires are mounted:
X Check the tire pressures (Y page 305).
X Restart the tire pressure loss warning
system (Y page 305).
For more information on driving with the
emergency spare wheel, see ( Y page 325).Snow chains
G
WARNING
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:
R never mount snow chains on the rear
wheels
R only 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 vehicle or tires, observe the "Wheel and
tire combinations" section under "Tires and
wheels".
For safety reasons, Mercedes-Benz
recommends 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. If you intend to mount snow chains, please
bear the following points in mind:
R
Snow chains may not be mounted on all
wheel/tire combinations. Permissible
wheel-tire combinations (Y page 323).
R Only 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.
R Local regulations may restrict the use of
snow chains. Observe the appropriate
regulations if you wish to mount snow
chains.
R Do not exceed the maximum permissible
speed of 30 mph (50 km/h).
R When snow chains

are installed, never use
Active Parking Assist (Y page 172).
i You may wish to deactivate
ESP ®
(Y page 62) when pulling away with
snow chains installed. You can thereby
allow the wheels to spin in a controlled
manner, achieving an increased driving
force (cutting action).
For more information on driving with the
emergency spare wheel, see ( Y page 325). Tire pressure
Tire pressure specifications
G
WARNING
Tires with tire pressures that are too low or
too high are associated with the following
hazards:
R they can burst,

in particular if the vehicle is
heavily laden or when driven at high
speeds.
R the tires can wear excessively and/or
unevenly, which can severely impair tire
traction.
R the driving, steering and braking
characteristics may be severely impaired.
There is a risk of accident. Tire pressure
301
Wheels and tires
ZProCarManuals.com

Follow recommended tire inflation pressures
and check the pressure of all the tires
including the spare wheel:
R
monthly, at least
R if the load changes
R before beginning a long journey
R under different operating conditions, e.g.
off-road driving
If necessary, correct the tire pressure.
Use a suitable pressure gauge to check the
tire pressure. The outer appearance of a tire
does not permit
any reliable conclusion about
the tire pressure. On vehicles equipped with
the electronic tire pressure monitor, the tire
pressure can be checked in the on-board
computer.
The recommended tire pressures for the tires
mounted at the factory can be found on the
labels described here.
1.) Tire and Loading Information placard
on the B-pillar on the driver's side of the
vehicle ( Y page 306).
The Tire and Loading Information placard
contains the recommended

tire pressures for
cold tires. The recommended tire pressures
are valid for the maximum permissible load
and up to the maximum permissible vehicle
speed. :
Recommended tire pressures
Option 2) Tire pressure table on the inside
of the fuel filler flap.
The tire pressure table contains the
recommended pressures for cold tires for various operating conditions, i.e. differing
load and speed conditions.
i
Specifications shown in the examples of
tire pressure tables are for illustration
purposes only. Tire

pressure specifications
are vehicle-specific and may deviate from
the data shown here. Tire pressure
specifications applicable to your vehicle
are located in your vehicle's tire pressure
table. Example: tire pressure table for all tires permitted
for this vehicle by the factory
If a
tire

size precedes a tire pressure, the tire
pressure information following is only valid
for that tire size. The load conditions "partially
laden" and "fully laden" are defined in the
table for different numbers of occupants and
amounts of luggage. The actual number of
seats may differ. Example: tire pressure table with tire dimensions
Some tire pressure tables show only the rim
diameters instead of the full tire size, e.g.
R18. Rim diameter

is part of the tire size and302
Tire pressure
Wheels and tires
ProCarManuals.com

can be found on the tire sidewall
(Y page 313).
If the tire pressures have been set to the
lower values for lighter loads and/or lower
road speeds, the pressures should be reset
to the higher values:
R
if you want to drive with an increased load
and/or
R if you want to drive at higher road speeds.
i The tire pressures for increased loads
and/or higher road speeds, shown in the
tire pressure table, may have a negative
effect on driving comfort.
If the tire pressure is not set correctly, this
can lead to
an excessive build up of heat and
a sudden loss of pressure.
For more information, contact a qualified
specialist workshop. Important notes on tire pressure
G
WARNING
If the tire pressure drops repeatedly, the
wheel, valve or tire may be damaged. Tire
pressure that is too low may result in a tire
blow-out. There is a risk of an accident.
R Check the tire for foreign objects.
R Check whether the

wheel is losing air or the
valve is leaking.
If you are unable to rectify the damage,
contact a qualified specialist workshop. G
WARNING
If you fit unsuitable accessories onto tire
valves, the tire

valves may be overloaded and
malfunction, which can cause tire pressure
loss. Due to their design, retrofitted tire
pressure monitors keep the tire valve open.
This can also result in tire pressure loss. There
is a risk of an accident.
Only screw the standard valve cap or other
valve caps approved by Mercedes-Benz for
your vehicle onto the tire valve.
Use a suitable pressure gauge to check the
tire pressure. The outer appearance of a tire
does not permit any reliable conclusion about
the tire pressure.
The tire temperature and pressure increase
when the vehicle is in motion. This is
dependent on the driving speed and the load.
Therefore, you should only correct tire
pressures when the tires are cold.
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)
The tire temperature changes depending on
the outside temperature, the vehicle speed
and the tire load. If the tire temperature
changes by 18 ‡ (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. Tire pressure
303
Wheels and tires Z
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