2010 MERCEDES-BENZ R320 wheel size

The Tire and Loading Information placard lists
the recommended cold tire inflation
pressures
: for maximum loaded vehicle
weight. The tire inflation pressures listed
apply to the tires installed as original
equipment.
Important notes on tire inflation
pressure G
Warning!
If the tire inflation pressure drops repeatedly,
check the tires for punctures from foreign
objects and/or whether air is leaking from the
valves or from around the rim.
Tire temperature and tire inflation pressure
are also increased while driving, depending
on the driving speed and the tire load.
If you will be driving your vehicle at high
speeds of 100 mph (160 km/h) or higher,
where it is legal and conditions allow, consult
the tire inflation pressure label on the inside
of the fuel filler flap on how to adjust the cold
tire inflation pressure. If you do not adjust the
tire inflation pressure, excessive heat can
build up and result in sudden tire failure.
If you are not sure about the proper tire
inflation, contact an authorized Mercedes-
Benz Center.
i Driving comfort may be reduced when the
tire inflation pressure is adjusted to the
value for speeds above 100 mph
(160 km/h) as specified on the tire inflation
pressure label located on the inside of the
fuel filler flap. Make sure to readjust the tire inflation
pressure for normal driving speeds.
Supplemental tire inflation pressure
information for different loading conditions of
the vehicle can be found on the tire inflation
pressure label. The tire inflation pressure
label is located on the inside of the fuel filler
flap.
For the tire inflation pressure for spare
wheels such as Minispare wheels or spare
wheels with collapsible tire refer to
R
the yellow label on the spare wheel rim
R the “Technical data” section of this
Operator’s Manual ( Y page 350)
R the Tire and Loading Information placard on
the driver’s door B-pillar
For the tire inflation pressure for full-size
spare wheels refer to
R the Tire and Loading Information placard on
the driver’s door B-pillar
R the tire inflation pressure label on the
inside of the fuel filler flap
Unless specified otherwise, the tire inflation
pressures on the tire inflation pressure label
are valid for all approved, factory-equipped
tires. When a tire size is specified, the tire
inflation pressure that follows applies to that
particular tire size only.
i Data shown on tire inflation pressure
label examples are for illustration purposes
only. Tire inflation pressure data are
specific to each vehicle and may vary from
data shown in the following illustrations.
Refer to the tire inflation pressure label on
vehicle for actual data specific to your
vehicle. Tires and wheels
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Example illustration: Tire inflation pressures for all
approved, factory equipped tires
Some tire inflation pressure labels may only
show the rim diameter instead of the entire
tire size, e.g. R 18 or 18".
The rim diameter is part of the tire size as
specified on the tire sidewall (Y page 245).
Example illustration: Tire inflation pressures
specific to rim diameter
i
When towing a trailer, inflate the tires to
the tire inflation pressure as specified for a
fully loaded vehicle.
Potential problems associated with
underinflated and overinflated tires Underinflated tires
G
Warning!
Follow recommended tire inflation pressures.
Do not underinflate tires. Underinflated tires
wear excessively and/or unevenly, adversely
affect handling and fuel economy, and are
more likely to fail from being overheated. Underinflated tires can
R
cause excessive and uneven tire wear
R adversely affect fuel economy
R lead to tire failure from being overheated
R adversely affect handling characteristics
Overinflated tires G
Warning!
Follow recommended tire inflation pressures.
Do not overinflate tires. Overinflated tires can
adversely affect handling and ride comfort,
wear unevenly, increase stopping distance,
and result in sudden deflation (blowout)
because they are more likely to become
punctured or damaged by road debris,
potholes etc.
Overinflated tires can
R adversely affect handling characteristics
R cause uneven tire wear
R be more prone to damage from road
hazards
R adversely affect ride comfort
R increase stopping distance Checking tire inflation pressure
Safety notes G
Warning!
Follow recommended tire inflation pressures.
Do not underinflate tires. Underinflated tires
wear excessively and/or unevenly, adversely
affect handling and fuel economy, and are
more likely to fail from being overheated.
Do not overinflate tires. Overinflated tires can
adversely affect handling and ride comfort,
wear unevenly, increase stopping distance,
and result in sudden deflation (blowout)
because they are more likely to become
punctured or damaged by road debris,
potholes etc. 230
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The TPMS is equipped with a combination low
tire pressure/ TPMS malfunction telltale in
the
instrument cluster. Depending on how the
telltale illuminates, it indicates a low tire
pressure condition or a malfunction in the
TPMS system itself:
R If the telltale illuminates continuously, one
or more of your tires is significantly
underinflated. There is no malfunction in
the TPMS.
R If the telltale flashes for 60 seconds and
then stays illuminated, the TPMS system
itself is not operating properly.
The TPMS only functions on wheels that are
equipped with the proper electronic sensors. G
Warning!
The TPMS does not indicate a warning for
wrongly selected inflation pressures. Always
adjust

tire inflation pressure according to the
Tire and Loading Information placard or the
supplemental tire inflation pressure
information on the inside of the fuel filler flap.
The TPMS is not able to issue a warning due
to a sudden dramatic loss of pressure (e.g. tire
blowout caused by a foreign object). In this
case bring the vehicle to a halt by carefully
applying the brakes and avoiding abrupt
steering maneuvers. G
Warning!
Each tire, including the spare (if provided),
should be checked at least once a month
when cold and inflated to the inflation
pressure recommended by the vehicle
manufacturer on the Tire and Loading
Information placard on the driver’s door B-
pillar

or the tire inflation 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 inflation pressure label, you should
determine the proper tire inflation 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.
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 1 minute and then
remain continuously illuminated. This
sequence will continue upon subsequent
vehicle start-ups 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 If a condition causing the TPMS to
malfunction develops, it may take up to
10 minutes for the system to signal a Tires and wheels
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punctured or damaged by road debris,
potholes etc.
i
For illustration purposes only. Actual data
on tires are specific to each vehicle and
may vary from data shown in above
illustration.
This is the maximum permissible tire inflation
pressure : for the tire.
Always follow the recommended tire inflation
pressure ( Y page 228) for proper tire
inflation. Loading the vehicle
Two labels on your vehicle show how much
weight it may properly carry.
(1) The Tire and Loading Information placard can be found on the driver’s door
B-pillar. This placard tells you important
information about the number of people
that can be in the vehicle and the total
weight that can be carried in the vehicle.
It also contains information on the proper
size and recommended tire inflation
pressures for the original equipment tires
on your vehicle.
(2) The certification label, also found on the driver’s door B-pillar. It tells you about the
gross weight capacity of your vehicle,
called the Gross Vehicle Weight Rating
(GVWR). The GVWR includes the weight
of the vehicle, all occupants, fuel and
cargo. The certification label also tells you about the front and rear axle weight
capacity, called the Gross Axle Weight
Rating (GAWR).
The GAWR is the total allowable weight
that can be carried by a single axle (front
or rear). Never exceed the GVWR or
GAWR for either the front axle or rear
axle.
:
Driver’s door B-pillar
Following is a discussion on how to work with
the information contained on the Tire and
Loading Information placard with regards to
loading your vehicle.
Tire and Loading Information G
Warning!
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. 236
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X
Step 5: Determine the combined weight of
luggage and cargo being loaded on the
vehicle. That weight may not safely exceed
the available cargo and luggage load
capacity calculated in step 4.
X Step 6 (if applicable): If your vehicle will
be towing a trailer, load from your trailer
will be transferred to your vehicle. Consult
this

manual to determine how this reduces
the available cargo and luggage load
capacity of your vehicle ( Y page 240).
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 1 500 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 237).238
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tests, and does not include acceleration,
cornering, hydroplaning, or peak traction
characteristics.
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
measured under controlled conditions on
specified
government test surfaces of asphalt
and concrete. A tire marked C may have poor
traction performance. G
Warning!
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 a dry road.
You should pay particular attention to the
condition of the road whenever the outside
temperature is close to the freezing point.
Mercedes-Benz recommends winter tires
(Y page 251) with a minimum tread depth of
approximately 1
/ 6 in (4 mm) on all four wheels
for the winter season to ensure normal
balanced handling characteristics. On
packed snow, they can reduce your stopping
distance compared to summer tires.
Stopping distance, however, is still
considerably greater than when the road is
not covered with snow or ice. Exercise
appropriate caution.
! Avoid spinning of a drive wheel. This may
cause serious damage to the drivetrain
which is not covered by the Mercedes-Benz
Limited Warranty.
Temperature G
Warning!
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, 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. 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. Rotating tires
G
Warning!
Rotate front and rear wheels only if the tires
are of the same dimension.
If your vehicle is equipped with mixed-size
tires

(different tire dimensions front vs. rear),
tire rotation is not possible. 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).
Only use genuine Mercedes-Benz wheel bolts
specified for your vehicle’s rims.
Tire rotation can be performed on vehicles
with tires of the same dimension all around.
If your vehicle is equipped with tires of the
same dimension all around, tires can be
rotated, observing a front-to-rear rotation
pattern that will maintain the intended
rotation (spinning) direction of the tire
(Y page 240).
In some cases, such as when your vehicle is
equipped with mixed-size tires (different tire Tires and wheels
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dimension front vs. rear), tire rotation is not
possible.
If applicable to your vehicle’s tire
configuration, tires can be rotated according
to the tire manufacturer’s recommended
intervals in the tire manufacturer’s warranty
pamphlet located in your vehicle literature
portfolio. If none is available, tires should be
rotated every 3 000 to 6
000 miles (5 000 to
10 000 km), or sooner if necessary, according
to the degree of tire wear. The same rotation
(spinning) direction must be maintained.
Rotate tires before the characteristic tire
wear pattern becomes visible (shoulder wear
on front tires and tread center wear on rear
tires).
Thoroughly clean the mounting face of wheels
and brake disks, i.e. the inner side of the
wheels/tires, during each rotation. Check for
and ensure proper tire inflation pressure.
For information on wheel change, see “Flat
tire” ( Y page 319). Tire labeling
Besides tire name (sales designation) and
manufacturer name, a number of markings
can be found on a tire.
Following are some explanations for the
markings on your vehicle’s tires: :
Uniform Tire Quality Grading Standards
(Y page 242)
; DOT, Tire Identification Number
(Y page 247)
= Maximum tire load ( Y page 240)
? Maximum tire inflation pressure
(Y page 235)
A Manufacturer
B Tire ply material ( Y page 248)
C Tire size designation, load and speed
rating (Y page 245)
D Load identification ( Y page 247)
E Tire name
i For illustration purposes only. Actual data
on tires are specific to each vehicle and
may vary from data shown in above
illustration.
For more information, see “Rims and tires”
(Y page 347). 244
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Tire size designation, load and speed
rating
:
Tire width
; Aspect ratio in %
= Radial tire code
? Rim diameter
A Load index
B Speed symbol
i For illustration purposes only. Actual data
on tires are specific to each vehicle and
may vary from data shown in above
illustration.
General: Depending on the design standards
used, the tire size molded into the sidewall
may have no letter or a letter preceding the
tire size designation.
No letter preceding the size designation (as
illustrated above): Passenger car tire based
on European design standards.
Letter “P” preceding the size designation:
Passenger car tire based on U.S. design
standards.
Letter “LT” preceding the size designation:
Light Truck tire based on U.S. design
standards.
Letter “T” preceding the size designation:
Temporary spare tires which are high
pressure compact spares designed for
temporary emergency use only.
Tire width
Tire width : indicates the nominal tire width
in millimeters. Aspect ratio
Aspect ratio
; is the dimensional
relationship between tire section height and
section width and is expressed in percentage.
The aspect ratio is arrived at by dividing
section height by section width.
Tire code
Tire code = indicates the tire construction
type. The “R” stands for radial tire type. Letter
“D” means diagonal or bias ply construction;
letter “B” means belted-bias ply construction.
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 ZR 18). For
additional information, see “Tire speed
rating” (Y page 246).
Rim diameter
Rim diameter ? is the diameter of the bead
seat, not the diameter of the rim edge. The
rim diameter is indicated in inches (in).
Load index G
Warning!
The tire load rating must always be at least
half of the GAWR of your vehicle. Otherwise,
tire failure may be the result which may cause
an accident and/or serious injury to you or
others.
Always replace rims and tires with the same
designation, manufacturer and type as shown
on the original part. G
Warning!
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.
Load index A is a numerical code associated
with the maximum load a tire can support. Tires and wheels
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