2012 MERCEDES-BENZ E-Class WAGON wheel size

R18. The rim diameter is part of the tire size
and can be found on the tire sidewall
( Y page 364).
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.
Option 3) The tire pressure for the
emergency/collapsible spare wheel
(depending on vehicle equipment) can be
found:
R printed in yellow on the rim of the
emergency/collapsible spare wheel
R in the "Wheel and tire combinations"
section ( Y page 371) in this manual
R on the Tire and Loading Information placard
on the B-pillar on the driver's side.
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 further information, consult a qualified
specialist workshop, e.g. an authorized
Mercedes-Benz Center.
Important notes on tire pressureGWARNING
Should the tire pressure drop repeatedly:
R check the tire for foreign bodies.
R check whether the wheel is losing air or the
valve is leaking.
R make sure that only a valve cap approved
by Mercedes-Benz is used on the tire valve.
Tire pressures that are too low have a
negative effect on vehicle safety, which could
lead you to cause an accident.
To test tire pressure, use a suitable tire
pressure gauge. The outer appearance of a
tire does not permit any reliable conclusion
about the tire pressure. On vehicles equipped
with the electronic tire pressure monitoring
system, the tire pressure can be checked
using the on-board computer.
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 more 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 and 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 pressure351Wheels and tiresZ

XPress the a button.
The tire pressure values stored at the last
restart will continue to be monitored.
Tire pressure monitor
Important safety notes
If a tire pressure monitor system is installed,
the vehicle's wheels have sensors that
monitor the tire pressures in all four tires. The
tire pressure monitor warns you when the
pressure drops in one or more of the tires. The
tire pressure monitor only functions if the
correct wheel electronics units are installed
on all wheels.
The tire pressure monitor has a yellow
warning lamp in the instrument cluster for
indicating pressure loss/malfunctions (USA)
or pressure loss (Canada). Whether the
warning lamp flashes or lights up indicates
whether a tire pressure is too low or the tire
pressure monitoring system is
malfunctioning:
R if the warning lamp is lit continuously, the
tire pressure on one or more tires is
significantly too low. The tire pressure
monitor is not malfunctioning.
R USA only: if the warning lamp flashes for
60 seconds and then remains lit constantly,
the tire pressure monitor is malfunctioning.
GWARNING
Each tire, including the spare (if provided),
should be checked at least once a month
when cold and inflated to the pressure
recommended by the vehicle manufacturer
on the Tire and Loading Information placard
on the driver's door B-pillar or the tire
pressure label on the inside of the fuel filler
flap. If your vehicle has tires of a different size
than the size indicated on the Tire and Loading
Information placard or the tire pressure label,
you should determine the proper tire pressure
for those tires.
As an added safety feature, your vehicle has
been equipped with a tire pressure monitoring
system (TPMS) that illuminates a low tire
pressure telltale when one or more of your
tires are significantly underinflated.
Accordingly, when the low tire pressure
telltale illuminates, you should stop and check
your tires as soon as possible, and inflate
them to the proper pressure. Driving on a
significantly underinflated tire causes the tire
to overheat and can lead to tire failure.
Underinflation also reduces fuel efficiency
and tire tread life, and may affect the vehicle's
handling and stopping ability.
Please note that the TPMS is not a substitute
for proper tire maintenance, and it is the
driver's responsibility to maintain correct tire
pressure, even if underinflation has not
reached the level to trigger illumination of the
TPMS low tire pressure telltale.
USA only:
Your vehicle has also been equipped with a
TPMS malfunction indicator to indicate when
the system is not operating properly. The
TPMS malfunction indicator is combined with
the low tire pressure telltale. When the
system detects a malfunction, the telltale will
flash for approximately one minute and then
remain continuously illuminated. This
sequence will be repeated every time the
vehicle is started as long as the malfunction
exists.
When the malfunction indicator is illuminated,
the system may not be able to detect or signal
low tire pressure as intended. TPMS
malfunctions may occur for a variety of
reasons, including the installation of
incompatible replacement or alternate tires
or wheels on the vehicle that prevent the
TPMS from functioning properly. Always
check the TPMS malfunction telltale after
replacing one or more tires or wheels on your
vehicle to ensure that the replacement or
alternate tires and wheels allow the TPMS to
continue to function properly.
i USA only:Tire pressure355Wheels and tiresZ

If you wish to cancel the restart:XPress the % button.
The tire pressure values stored at the last
restart will continue to be monitored.
Loading the vehicle
Instruction labels for tires and loads
GWARNING
Do not overload the tires by exceeding the
specified load limit as indicated on the Tire
and Loading Information placard on the
driver's door B-pillar. Overloading the tires
can overheat them, possibly causing a
blowout. Overloading the tires can also result
in handling or steering problems, or brake
failure.
Two instruction labels on your vehicle show
the maximum possible load.
(1)The Tire and Loading Information placard
on the B-pillar on the driver's side. The
Tire and Loading Information placard
shows the maximum permissible number
of occupants and the maximum
permissible vehicle load. It also contains
details of the tire sizes and
corresponding pressures for tires
mounted at the factory.(2)The vehicle identification plate is on the
B-pillar on the driver's side. The vehicle
identification plate informs you of the
gross vehicle weight rating. It is made up
of the vehicle weight, all vehicle
occupants, the fuel and the cargo. You
can also find information about the
maximum gross axle weight rating on the
front and rear axle.
The maximum gross axle weight rating is
the maximum weight that can be carried
by one axle (front or rear axle). Never
exceed the maximum load or the
maximum gross axle weight rating for the
front or rear axle.
B-pillar (example: Sedan)
:B-pillar, driver's side
Maximum permissible gross vehicle
weight rating
i The specifications shown on the Tire and
Loading Information placard in the
illustration are examples. The maximum
permissible gross vehicle weight rating is
vehicle-specific and may differ from that in
the illustration. You can find the valid
maximum permissible gross vehicle weight
rating for your vehicle on the Tire and
Loading Information placard.
XThe Tire and Loading Information placard
gives you details on maximum permissible
gross vehicle weight rating :: "The gross
weight of occupants and luggage must
never exceed XXX kilograms or XXX
pounds."
The gross weight of all vehicle occupants,
cargo, luggage and trailer load/noseweight (if
applicable) must not exceed the specified
value.
358Loading the vehicleWheels and tires

Example: step 1 to 3
The following table shows examples on how to calculate total and cargo load capacities with
varying seating configurations and number and size of occupants. The following examples use
a load limit of 1500 lbs. This is for illustration purposes only. Make sure you are using the
actual load limit for your vehicle stated on the vehicle’s Tire and Loading Information placard
( Y page 359).
Example 1Example 2Example 3Step 1Combined maximum
weight of occupants
and cargo (data from
the Tire and Loading
Information placard)1500 lbs
(680 kg)1500 lbs
(680 kg)1500 lbs
(680 kg)Example 1Example 2Example 3Step 2Number of people in
the vehicle (driver
and occupants)531Distribution of the
occupantsFront: 2
Rear: 3Front: 1
Rear: 2Front: 1Weight of the
occupantsOccupant 1:
150 lbs (68 kg)
Occupant 2:
180 lbs (82 kg)
Occupant 3:
160 lbs (73 kg)
Occupant 4:
140 lbs (63 kg)
Occupant 5:
120 lbs (54 kg)Occupant 1:
200 lbs (91 kg)
Occupant 2:
190 lbs (86 kg)
Occupant 3:
150 lbs (68 kg)Occupant 1:
150 lbs (68 kg)Gross weight of all
occupants750 lbs (340 kg)540 lbs (245 kg)150 lbs (68 kg)360Loading the vehicleWheels and tires

the tire's ability to stop on a wet surface as
measured under controlled conditions on
specified government test surfaces of asphalt
and concrete. A tire marked C may have poor
traction performance.GWARNING
If ice has formed on the road, tire traction will
be substantially reduced. Under such weather
conditions, drive, steer and brake with
extreme caution.
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
conditions when temperatures are around
the freezing point.
Mercedes-Benz recommends a minimum tire
tread depth of 1
/ 6 in (4 mm) for all four winter
tires ( Y page 174) to maintain normal driving
characteristics in winter. Winter tires can
reduce the braking distance on snow covered
surfaces in comparison to summer tires.
Stopping distance, however, is still
considerably greater than when the road is
not covered with ice or snow. Take
appropriate care when driving.
! Avoid wheelspin. This can lead to damage
to the drive train.
Temperature
GWARNING
The temperature grade for this tire is
established for a tire that is properly inflated
and not overloaded. Excessive speed,
underinflation, 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. These represent 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. Sustained 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
Tire labeling overview
The following markings are on the tire in
addition to the tire name (sales designation)
and the manufacturer's name:
:Uniform tire Quality Grading Standard
( Y page 368);DOT, Tire Identification Number
( Y page 366)=Maximum tire load ( Y page 361)?Maximum tire pressure ( Y page 352)AManufacturerBTire material ( Y page 367)CTire size designation, load-bearing
capacity and speed rating ( Y page 364)Tire labeling363Wheels and tiresZ

DLoad index (Y page 366)ETire name
i
Tire data is vehicle-specific and may
deviate from the data in the example.
Tire size designation, load-bearing
capacity and speed rating
:Tire width;Nominal aspect ratio in %=Tire code?Rim diameterALoad bearing indexBSpeed rating
i Tire data is vehicle-specific and may
deviate from the data in the example.
General: depending on the manufacturer's
standards, the size imprinted in the tire wall
may not contain any letters or may contain
one letter that precedes the size description.
If there is no letter preceding the size
description (as shown above): these are
passenger vehicle tires according to
European manufacturing standards.
If "P" precedes the size description: these are
passenger vehicle tires according to U.S.
manufacturing standards.
If "LT" precedes the size description: these
are light truck tires according to U.S.
manufacturing standards.
If "T" precedes the size description: these are
compact emergency spare wheels at high tire
pressure, to be used only temporarily in an
emergency.
Tire width: tire width : shows the nominal
tire width in millimeters.
Nominal aspect ratio: aspect ratio ; is the
size ratio between the tire height and the tire
width and is shown in percent. The aspect
ratio is calculated by dividing the tire width by
the tire height.
Tire code: tire code = specifies the tire type.
"R" represents radial tires. "D" represents
diagonal tires, "B" represents diagonal radial
tires.
Optionally, tires with a maximum speed of
over 149 mph(240 km/h) may have "ZR" in
the size description depending on the
manufacturer (e.g. 245/40 ZR 18).
Rim diameter: rim diameter ? is the
diameter of the bead seat, not the diameter
of the rim flange. The rim diameter is
specified in inches (in).
Load bearing index: load bearing index A
is a numerical code which specifies the
maximum load-bearing capacity of a tire.GWARNING
The tire load rating must always be at least
half of the GAWR of your vehicle. Otherwise,
sudden tire failure may be the result which
could cause an accident and/or serious injury
to you or others.
Always replace rims and tires with rims and
tires having the same specifications
(designation, manufacturer and type) as
shown on the original part.
GWARNING
Do not overload the tires by exceeding the
specified load limit as indicated on the Tire
and Loading Information placard on the
driver's door B-pillar. Overloading the tires
can overheat them, possibly causing a
blowout. Overloading the tires can also result
in handling or steering problems, or brake
failure.
364Tire labelingWheels and tires

Example:
The load bearing index 91 is equivalent to a
maximum load of 1356 lbs (615 kg) that the
tire can carry. For further information on the
maximum tire load in kilograms and pounds,
see ( Y page 361).
For further information on the load bearing
index, see Load index ( Y page 366).
Speed rating: speed rating B specifies the
approved maximum speed of the tire.GWARNING
Even when permitted by law, never operate a
vehicle at speeds greater than the maximum
speed rating of the tires.
Exceeding the maximum speed for which tires
are rated can lead to sudden tire failure,
causing loss of vehicle control and possibly
resulting in an accident and/or serious
personal injury and possible death, for you
and for others.
Regardless of the speed rating always
observe the speed limits. Drive carefully and
adapt your driving style to the traffic
conditions.
Summer tiresIndexSpeed ratingQUp to 100 mph (160 km/h)RUp to 106 mph (170 km/h)SUp to 112 mph (180 km/h)TUp to 118 mph (190 km/h)HUp to 130 mph (210 km/h)VUp to 149 mph (240 km/h)WUp to 168 mph (270 km/h)YUp to 186 mph (300 km/h)ZR...YUp to 186 mph (300 km/h)Summer tiresIndexSpeed ratingZR...(..Y)Above 186 mph (300 km/h)ZRAbove 149 mph (240 km/h)
R Optionally, tires with a maximum speed of
over 149 mph (240 km/h) may have "ZR"
in the size description depending on the
manufacturer (e.g. 245/40 ZR 18).
The service specifications consist of load
bearing index A and speed rating B.
R If the size description of your tire includes
"ZR" and there are no service
specifications, ask the tire manufacturer in
order to find out the maximum speed.
If a service specification is available, the
maximum speed is limited according to the
speed rating in the service specification.
Example: 245/40 ZR 18 97 Y. In this
example, "97 Y" is the service specification.
The letter "Y" represents the speed rating
and the maximum speed of the tire is
limited to 186 mph (300 km/h).
R Every tire that has a maximum speed above
186 mph (300 km/h) must have "ZR" in the
size description and the service
specification must be given in brackets.
Example: 275/40 ZR 18 (99 Y). The speed
rating "(Y)" shows that the maximum speed
of the tire is above 186 mph (300 km/h).
Ask the tire manufacturer to find out the
maximum speed.
All-weather tires and winter tiresIndexSpeed ratingQ M+S 33Up to 100 mph (160 km/h)T M+S33Up to 118 mph (190 km/h)H M+S 33Up to 130 mph (210 km/h)V M+S33Up to 149 mph (240 km/h)33
Or M+S i for winter tires.Tire labeling365Wheels and tiresZ

The TIN is a unique identification number. The
TIN enables the tire manufacturers to inform
purchasers of recalls and other safety-
relevant matters. It makes it possible for the
purchaser to easily identify the affected tires.
The TIN is made up of manufacturer
identification code ;, tire size =, tire type
code ? and manufacturing date A.
i Tire data is vehicle-specific and may
deviate from the data in the example.
DOT (Department of Transportation): tire
symbol : indicates that the tire complies
with the requirements of the U.S. Department
of Transportation.
Manufacturer identification code:
manufacturer identification code ; provides
details on the tire manufacturer. New tires
have a code with two symbols. Retreaded
tires have a code with four symbols.
Further information about retreaded tires
( Y page 346).
Tire size: identifier = describes the tire size.
Tire type code: tire type code ? can be
used by the manufacturer as a code to
describe specific characteristics of the tire.
Date of manufacture: date of manufacture
A provides information about the age of a
tire. The first and second positions represent
the week of manufacture, starting with "01"
for the first calendar week. Positions three
and four represent the year of manufacture.
For example, a tire that is marked with
"3208", was manufactured in week 32 in
2008.Tire characteristics
i Tire data is vehicle-specific and may
deviate from the data in the example.
This information describes the tire cord and
the number of layers in sidewall : and under
the tread ;.
Definition of terms for tires and
loading
Tire ply composition and material
used
Describes the number of plies or the number
of layers of rubber-coated fabric in the tire
tread and sidewall. These are made of steel,
nylon, polyester and other materials.
Bar
Metric unit for tire pressure. There are
14.5038 pounds per square inch (psi) to
1 bar; there are 100 kilopascals (kPa) to
1 bar.
DOT (Department of Transportation)
DOT marked tires fulfill the requirements of
the United States Department of
Transportation.
Definition of terms for tires and loading367Wheels and tiresZ