2010 MERCEDES-BENZ R320 wheel size

For example, a load rating of 91 corresponds
to a maximum load of 1356 lb (615 kg) the
tire is designed to support. See also
“Maximum
tire load” (Y page 240) where the
maximum load associated with the load index
is indicated in kilograms and lbs.
For additional information on the load index,
see “Load identification” (Y page 247).
Speed symbol G
Warning!
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 tire speed rating, local
speed limits should be obeyed. Use prudent
driving speeds appropriate to prevailing
conditions.
Speed symbol B indicates the approved
maximum speed (tire speed rating) for the
tire.
Summer tires Index Speed rating
Q up to 100 mph (160 km/h)
R up to 106 mph (170 km/h)
S up to 112 mph (180 km/h)
T up to 118 mph (190 km/h)
H up to 130 mph (210 km/h)
V up to 149 mph (240 km/h)
W up to 168 mph (270 km/h)
Y up to 186 mph (300 km/h)
ZR...Y up to 186 mph (300 km/h) Index Speed rating
ZR...(..Y) above 186 mph (300 km/h)
ZR above 149 mph (240 km/h)
R
At the tire manufacturer’s option, any tire
with a speed capability above 149 mph
(240 km/h) can include a “ZR” in the size
designation (for example: 245/40 ZR18).
To determine the maximum speed
capability of the tire, the service
description

for the tire must be referred to.
The service description is comprised of
load index A and speed symbol B.
If your tire includes “ZR” in the size
designation and no service description is
given, the tire manufacturer must be
consulted for the maximum speed
capability.
If a service description is given, the speed
capability is limited by the speed symbol in
the service description. Example:
245/40 ZR18 97Y. In this example, “97Y”
is the service description. The letter “Y”
designates the speed rating and the speed
capability of the tire is limited to 186 mph
(300 km/h).
R Any tire with a speed capability above
186 mph (300 km/h) must include a “ZR”
in the size designation AND the service
description must be placed in parenthesis.
Example: 275/40 ZR 18 (99Y). The “(Y)”
speed symbol in parenthesis designates
the maximum speed capability of the tire
as being above 186 mph (300 km/h).
Consult the tire manufacturer for the actual
maximum permissible speed of the tire.
All-season and winter tires Index Speed rating
Q M+S
14 up to 100 mph (160 km/h)
T M+S
14 up to 118 mph (190 km/h)
14
or M+S ifor winter tires 246
Tires and wheels
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The TIN is a unique identifier. The TIN
facilitates efforts by tire manufactures to
notify purchasers in recall situations or other
safety matters concerning tires. It gives
purchasers the means to easily identify such
tires.
The TIN is comprised of “Manufacturer’s
identification mark” ;, “Tire size”
=, “Tire
type code” ? and “Date of manufacture”
A.
i For illustration purposes only. Actual data
on tires are specific to each vehicle and
may vary from data shown in above
illustration.
DOT (Department of Transportation) Tire branding symbol
: denotes that the tire
meets requirements of the U.S. Department
of Transportation.
Manufacturer’s identification mark Manufacturer’s identification mark ;
denotes the tire manufacturer.
New tires have a mark with two symbols.
Retreaded tires have a mark with four
symbols. For more information on retreaded
tires, see (
Y page 227).
Tire size Code
= indicates the tire size. Tire type code Tire type code
? may, at the option of the
manufacturer, be used as a descriptive code
for identifying significant characteristics of
the tire.
Date of manufacture The date of manufacture
A identifies the
week and year of manufacture.
The first two figures identify the week,
starting with “01” to represent the first full
week of the calendar year. The second two
figures represent the year.
For example, “3208” represents the 32nd
week of 2008. Tire ply material
i
For illustration purposes only. Actual data
on tires are specific to each vehicle and
may vary from data shown in above
illustration.
This marking tells you about the type of cord
and number of plies in the sidewall : and
under the tread ;. Tire and loading terminology
Accessory weight The combined weight (in excess of those
standard items which may be replaced) of
automatic transmission, power steering,
power brakes, power windows, power seats,248
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Maximum loaded vehicle weight
The sum of curb weight, accessory weight,
total load limit, and production options
weight.
Maximum permissible tire inflation
pressure
This number is the greatest amount of air
pressure that should ever be put in the tire.
Normal occupant weight
The number of occupants the vehicle is
designed to seat, multiplied by 68 kilograms
(150 lb).
Occupant distribution
The distribution of occupants in a vehicle at
their designated seating positions.
Production options weight
The combined weight of those installed
regular production options weighing over
5 lbs (2.3 kilograms) in excess of those
standard items which they replace, not
previously considered in curb weight or
accessory weight, including heavy duty
brakes, ride levelers, roof rack, heavy duty
battery, and special trim.
PSI (Pounds per square inch)
A standard unit of measure for air pressure.
Recommended tire inflation pressure
The recommended tire inflation pressure for
normal
driving conditions is listed on the Tire
and Loading Information placard located on
the driver’s door B-pillar. It provides best
handling, tread life and riding comfort.
Supplemental information pertaining to
special driving situations can be found on the
tire inflation pressure label on the inside of
the fuel filler flap. Rim A metal support for a tire or a tire and tube
assembly upon which the tire beads are
seated.
Sidewall
The portion of a tire between the tread and
the bead.
TIN (Tire Identification Number)
Unique identifier which facilitates efforts by
tire manufacturers to notify purchasers in
recall situations or other safety matters
concerning tires and gives purchasers the
means

to easily identify such tires. The TIN is
comprised of “Manufacturer’s identification
mark”, “Tire size”, “Tire type code” and “Date
of manufacture”.
Tire ply composition and material used This indicates the number of plies or the
number of layers of rubber-coated fabric in
the tire tread and sidewall. Tire
manufacturers also must indicate the ply
materials in the tire and sidewall, which
include steel, nylon, polyester, and others.
Tire speed rating
Part of tire designation (speed symbol);
indicates the speed range for which a tire is
approved.
Total load limit
Rated cargo and luggage load plus
68 kilograms (150 lb) times the vehicle’s
designated seating capacity.
Traction
The adhesive friction of a tire on a surface on
which

it moves. The amount of grip provided. 250
Tires and wheels
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Snow chains
! Vehicles with Adaptive Damping System
(ADS):
When driving with snow chains, do not
select SPORT mode as this may result in
damage to your vehicle.
! Some tire sizes do not leave adequate
clearance for snow chains. To help avoid
serious damage to your vehicle or tires,
make sure the use of snow chains is
permissible as specified in the “Technical
data” section of this Operator’s Manual.
Snow chains should only be driven on snow-
covered roads at speeds not to exceed
30 mph (50 km/h)
. Remove chains as soon
as possible when driving on roads without
snow.
Observe the following guidelines when using
snow chains:
R Use of snow chains is not permissible with
all wheel/tire combinations ( Y page 347).
R Use snow chains in pairs and on rear
wheels only. Follow the manufacturer’s
mounting instructions.
! If snow chains are mounted to the front
wheels, they may scrape against the body
or axle components. The tires or the vehicle
could be damaged as a result.
R Only use snow chains that are approved by
Mercedes-Benz. Any authorized Mercedes-
Benz Center will be glad to advise you on
this subject.
R Use of snow chains may be prohibited
depending on location. Always check local
and state laws before installing snow
chains.
R Do not use snow chains on the spare wheel.
i When driving with snow chains, you may
wish to switch off the ESP ®
(Y page 65)
before setting the vehicle in motion. This
will improve the vehicle’s traction. Winter driving instructions
G
Warning!
If the vehicle becomes stuck in snow, make
sure snow is kept clear of the exhaust pipe
and from around the vehicle with the engine
running. Otherwise, deadly carbon monoxide
(CO) gases may enter vehicle interior
resulting in unconsciousness and death.
To

assure sufficient fresh air ventilation, open
a window slightly on the side of the vehicle
not facing the wind. G
Warning!
The outside temperature indicator is not
designed to serve as an ice-warning device
and is therefore unsuitable for that purpose.
Indicated temperatures just above the
freezing

point do not guarantee that the road
surface is free of ice. The road may still be icy,
especially in wooded areas or on bridges. G
Warning!
On slippery road surfaces, never downshift in
order to obtain braking action. This could
result

in drive wheel slip and reduced vehicle
control. Your vehicle’s ABS will not prevent
this type of loss of control.
The most important rule for slippery or icy
roads is to drive sensibly and to avoid abrupt
acceleration, braking and steering
maneuvers. Do not use the cruise control
system under such conditions.
When the vehicle is in danger of skidding, shift
the automatic transmission to neutral
position N. Try to keep the vehicle under
control by corrective steering action.
i For information on driving with snow
chains, see “Snow chains” ( Y page 252).
Road salts and chemicals can adversely
affect braking efficiency. Increased pedal
force may become necessary to produce the
normal brake effect.
Depressing the brake pedal periodically when
traveling at length on salt-strewn roads can 252
Winter driving
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(80 km/h) or below with the recommended
tire inflation pressure.
X Contact an authorized Mercedes-Benz
Center

as soon as possible to obtain a new
TIREFIT kit.
X Bring used TIREFIT materials to an
authorized Mercedes-Benz Center for
proper disposal.
X Replace your TIREFIT container every
4 years. Replacement containers are
available

at any authorized Mercedes-Benz
Center. Mounting the spare wheel
Introduction X
Prepare the vehicle as described
(Y page 320).
X Take the following out of the vehicle:
R
spare wheel
R jack
R wheel wrench
R collapsible wheel chock
R alignment bolt
R electric air pump
For information on where to find the
respective items, see “Where will I find ...?”
(Y page 270) and ( Y page 272).
i Vehicles without spare wheel are not
factory-equipped

with the tools required for
a wheel change such as a jack or a wheel
wrench. Some tools required for a wheel
change are specific to your vehicle.
Contact an authorized Mercedes-Benz
Center to obtain the tools approved for
your vehicle. This section describes the
wheel change using the tools approved and
recommended for your vehicle. Lifting the vehicle G
Warning!
When jacking up the vehicle, only use the jack
which has been specifically approved by
Mercedes-Benz for your vehicle.
The

jack is designed exclusively for jacking up
the vehicle at the jack take-up brackets built
into both sides of the vehicle. Make sure the
jack arm is fully seated in the jack take-up
bracket. The jack must always be vertical
when in use, especially on inclines or
declines.
The jack is intended only for lifting the vehicle
briefly for wheel changes. It is not suited for
performing maintenance work under the
vehicle. To help avoid personal injury, use the
jack only to lift the vehicle during a wheel
change.
Never get beneath the vehicle while it is
supported by the jack. Keep hands and feet
away from the area under the lifted vehicle.
Always lower the vehicle onto sufficient
capacity jackstands before working under the
vehicle.
Always engage the parking brake firmly and
block the wheels with wheel chocks or other
sizeable objects before raising the vehicle
with the jack. Do not disengage the parking
brake while the vehicle is raised.
Make sure that the ground on which the
vehicle is standing and where you place the
jack is solid, level and not slippery. If
necessary, use a large underlay. On slippery
surfaces, such as tiled floors, you should use
a non-slip underlay, for example a rubber mat.
Do not use wooden blocks or similar objects
to support the jack. Otherwise the jack may
not be able to achieve its load-bearing
capacity if it is not at its full height.
Never start the engine when the vehicle is
raised.
Also observe the notes on the jack. 324
Flat tire
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X
Prevent the vehicle from rolling away by
blocking wheels with wheel chocks or other
sizeable objects.
When your vehicle is equipped with a wheel
chock, it is included with the vehicle tool kit
(Y page 270). For information on setting up
the collapsible wheel chock, see
(Y page 272). G
Warning!
Only jack up the vehicle on level ground or on
slight inclines/declines. Otherwise, the
vehicle could fall off the jack and injure you or
others.
Changing a wheel on a level surface Changing rear wheel on passenger side (example
illustration)
X
Place a wheel chock or other sizeable
object in front of and another wheel chock
or other sizeable object behind the wheel
that is diagonally opposite to the wheel
being changed.
Changing a wheel on a slight decline
Always try lifting the vehicle using the jack on
a level surface. However, should
circumstances require you to do so on a slight
decline: Changing wheel on passenger side (example
illustration)
X
Place wheel chocks or other sizeable
objects on the downhill side in front of both
wheels on the side opposite to the side on
which the wheel is to be changed.
Changing a wheel on a slight incline
Always try lifting the vehicle using the jack on
a level surface. However, should
circumstances require you to do so on a slight
incline: Changing wheel on passenger side (example
illustration)
X
Place wheel chocks or other sizeable
objects on the downhill side in front of both
wheels on the side opposite to the side on
which the wheel is to be changed. Flat tire
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X
Tighten the five wheel bolts evenly,
following the diagonal sequence illustrated
(: to A), until all bolts are tight. Observe
a tightening torque of 110 lb-ft (150 Nm). G
Warning!
Have the tightening torque checked after
changing a wheel. The wheels could come
loose if they are not tightened to a torque of
110 lb-ft (150 Nm).
X Fully collapse the jack to storage position,
see ( Y page 272).
X Store the jack and the other vehicle tools
in the designated storage space.
For information on storing the spare wheel
after it has been replaced by a regular road
wheel, see ( Y page 272).
i The damaged road wheel cannot be
stored in the spare wheel well under the
cargo compartment floor. It should be
transported in the cargo compartment
wrapped in a protective wrap.
i USA only:
Do not restart the tire inflation pressure
monitor until a full size wheel/tire with
functioning sensor has been placed back
into service on the vehicle. MOExtended system
The MOExtended system allows you to
continue driving your vehicle even if there is
a total loss of pressure in one or more tires. You may only use the MOExtended system in
conjunction with the tire pressure loss
warning system (
Y page 231) or the
Advanced TPMS (Y page 232).
The maximum distance in emergency mode
depends on the vehicle’s load. It is 50 miles
(80 km) if the vehicle is partially loaded and
18 miles (30 km) if the vehicle is fully loaded.
The point at which the maximum driving
distance in emergency mode begins is when
the warning message appears in the
multifunction display indicating that there is
a loss of tire inflation pressure.
X Do not exceed the maximum speed of
50 mph (80 km/h). G
Warning!
In emergency mode, your vehicle’s driving
characteristics are diminished in such
situations as:
R driving around curves
R while braking
R while accelerating rapidly
Therefore, your driving style must be adapted
accordingly. Avoid abrupt steering and driving
maneuvers, as well as driving over obstacles
(road curbs, potholes, or off-road areas). This
is especially important if the vehicle is heavily
loaded.
The emergency driving distance that can be
achieved greatly depends on the demands
placed on the vehicle. Depending on speed,
load, driving maneuvers, road conditions,
outside temperature, etc., the distance can be
significantly shorter or, if the vehicle is driven
cautiously, somewhat longer.
Do not continue driving in emergency mode if
R you notice knocking sounds
R the vehicle starts to shake
R smoke develops and you smell rubber
R ESP ®
is intervening continuously
R you notice tears on the tire sidewalls 330
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i
Vehicles with MOExtended system are
not factory-equipped with a TIREFIT kit.
When
retrofitting with tires that do not have
run-flat characteristics, you should also
equip your vehicle with a TIREFIT kit.
TIREFIT kits are available at any authorized
Mercedes-Benz Center.
! Using tires other than those approved by
Mercedes-Benz can have detrimental
effects, such as
R poor handling characteristics
R increased noise
R increased fuel consumption
Moreover, tires and rims not approved by
Mercedes-Benz may, under load, exhibit
dimensional variations and different tire
deformation characteristics that could
cause them to come into contact with the
vehicle body or axle parts. Damage to the
tires or the vehicle may be the result.
i Further information on tires and rims is
available at any authorized Mercedes-Benz
Center. The Tire and Loading Information
placard with the recommended tire
inflation pressures for cold tires is located
on the driver’s door B-pillar. Supplemental
tire inflation pressure information for
driving at high speeds or for vehicle loads
less than the maximum loaded vehicle
condition can be found on the tire inflation
pressure label. The tire inflation pressure
label is located on the inside of the fuel filler
flap. The tire inflation pressure should be
checked regularly and should only be
adjusted on cold tires. Follow tire
manufacturer’s maintenance
recommendation included with the vehicle.
For information on recommended tire
inflation pressure and supplemental tire
inflation pressure information for special
driving situations, see ( Y page 228). i
Please keep in mind that the vehicle must
be equipped
Rwith wheels of identical dimensions on
each axle (left and right)
R with tires of identical characteristics all
around, i.e. summer tires, winter tires,
all-season tires, or MOExtended tires etc.
i The following pages also list the approved
rim and tire sizes for equipping your vehicle
with winter tires. Winter tires are not
available as standard or optional factory
equipment, but can be purchased from an
authorized Mercedes-Benz Center.
Equipping your vehicle with winter tires
approved for your vehicle model may
require the purchase of rims of the
recommended size for use with these
winter tires. This depends on vehicle model
and the standard or optional factory-
equipped wheel rim/tire configuration on
your vehicle. For more information contact
an authorized Mercedes-Benz Center. 348
Rims and tires
Technical data
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