2015 MERCEDES-BENZ M-Class tire size

operating conditions, i.e. differing load and
speed conditions. Example: tire pressure table with tire dimensions
If a tire size precedes a tire pressure, the tirepressure 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. Some tire pressure tables show only the rim
diameters instead of the full tire size, e.g.
R18. The rim diameter is part of the tire size
and can be found on the tire sidewall
(Y page 417).
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 spe- cialist 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, con-
tact 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 pres- sure 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. On vehicles equipped with
the electronic tire pressure monitoring sys-
tem, 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 depend-
ent on the driving speed and the load.
Therefore, you should only correct tire pres-
sures when the tires are cold. Tire pressure
405Wheels and tires Z

Example: current tire pressure display
For information on the message display, refer to the "Checking the tire pressure electroni-
cally" section (Y page 410).
Important safety notes G
WARNING
Each tire, including the spare (if provided),
should be checked at least once a month
when cold and inflated to the pressure rec-
ommended 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 Infor-
mation 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 pres-
sure 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 underin-
flated tire causes the tire to overheat and can lead to tire failure. Underinflation also
reduces fuel efficiency and tire tread life, andmay affect the vehicle's handling and stop-
ping ability.
Please note that the TPMS is not a substitute
for proper tire maintenance, and it is the driv-
er'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 if 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 warning lamp will
flash for approximately a minute and then
remain continuously illuminated. This
sequence will be repeated every time the vehi- cle 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 malfunc-tions may occur for a variety of reasons,
including the mounting of incompatible
replacement or alternate tires or wheels on
the vehicle that prevent the TPMS from func-
tioning properly. Always check the TPMS mal-
function 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 prop-
erly.
It is the driver's responsibility to set the tire
pressure to that recommended for cold tires
which is suitable for the operating situation
(Y page 404). Note that the correct tire pres-
sure for the current operating situation must
first be taught-in to the tire pressure monitor. If there is a substantial loss of pressure, the
warning threshold for the warning message isaligned to the reference values taught-in.
Restart the tire pressure monitor after adjust-
ing the pressure of the cold tires
(Y page 411). The current pressures are
saved as new reference values. As a result, a
warning message will appear if the tire pres-
sure drops significantly.
The tire pressure monitor does not warn you
of an incorrectly set tire pressure. Observe
the notes on the recommended tire pressure
(Y page 404).
The tire pressure monitor is not able to warn
you of a sudden loss of pressure, e.g. if the Tire pressure
409Wheels and tires Z

Loading the vehicle
Instruction labels for tires and loads
G
WARNING
Overloaded tires can overheat, causing a
blowout. Overloaded tires can also impair the steering and driving characteristics and lead
to brake failure. There is a risk of accident.
Observe the load rating of the tires. The load
rating must be at least half of the GAWR of
your vehicle. Never overload the tires by
exceeding the maximum load.
Two instruction labels on your vehicle show
the maximum possible load.
(1) The Tire and Loading Information placard is 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 permis-
sible vehicle load. It also contains details
of the tire sizes and corresponding pres-
sures 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 occu-
pants, 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 maxi-
mum gross axle weight rating for the
front or rear axle. 0043
B-pillar, driver's side Maximum permissible gross vehicle
weight rating
X
Specification for maximum gross vehicle
weight 0043is listed in the Tire and Loading
Information placard: "The combined weight of occupants and cargo should never
exceed XXX kilograms or XXX lbs."
The gross weight of all vehicle occupants,
load and luggage must not exceed the speci-
fied value.
i The specifications shown on the Tire and
Loading Information placard in the illustra-
tion are examples. The maximum permis-
sible gross vehicle weight rating is vehicle- specific and may differ from that in the
illustration. You can find the valid maximum 412
Loading the vehicleWheels and tires

Example: steps 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 usea maximum load of 1,500 lbs (680 kg). This is for illustration purposes only. Make sure you
are using the actual load limit for your vehicle stated on your vehicle's Tire and Loading Infor- mation placard (Y page 412).
The greater the combined weight of the occupants, the lower the maximum luggage load.
Additional information when towing a trailer (Y page 257).
Step 1 Example 1 Example 2 Example 3
Combined 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)
Step 2
Example 1 Example 2 Example 3
Number of people in
the vehicle (driver
and occupants)
5 3 1
Distribution of the
occupants
Front: 2
Rear: 3 Front: 1
Rear: 2 Front: 1
Weight of the occu-
pants
Occupant 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
occupants
750 lbs (340 kg) 540 lbs (245 kg) 150 lbs (68 kg)414
Loading the vehicleWheels and tires

Tire labeling
Overview 0043
Uniform Tire Quality Grading Standard
(Ypage 421)
0044 DOT, Tire Identification Number
(Ypage 420)
0087 Maximum tire load (Y page 419)
0085 Maximum tire pressure (Y page 406)
0083 Manufacturer
0084 Tire material (Y page 420)
006B Tire size designation, load-bearing capa-
city and speed index (Y page 417)
006C Load index (Y page 419)
006D Tire name
The markings described above are on the tire in addition to the tire name (sales designa-
tion) and the manufacturer's name.
i Tire data is vehicle-specific and may devi-
ate from the data in the example.
Tire size designation, load-bearing
capacity and speed rating G
WARNING
Exceeding the stated tire load-bearing capa-
city and the approved maximum speed could
lead to tire damage or the tire bursting. There is a risk of accident. Therefore, only use tire types and sizes
approved for your vehicle model. Observe the
tire load rating and speed rating required for
your vehicle. 0043
Tire width
0044 Nominal aspect ratio in %
0087 Tire code
0085 Rim diameter
0083 Load bearing index
0084 Speed rating
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 descrip-
tion (as shown above): these are passenger
vehicle tires according to European manufac-
turing 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. manu-
facturing 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 width0043shows the nominal
tire width in millimeters.
Height-width ratio: aspect ratio0044is the
size ratio between the tire height and tire
width and is shown in percent. The aspect All about
wheels and tires
417Wheels and tires Z

ratio is calculated by dividing the tire width by
the tire height.
Tire code: tire code0087specifies 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 man-
ufacturer (e.g. 245/40 ZR 18).
Rim diameter: rim diameter0085is the diam-
eter of the bead seat, not the diameter of the
rim flange. The rim diameter is specified in
inches (in).
Load-bearing index: load-bearing index0083
is a numerical code that specifies the maxi-
mum load-bearing capacity of a tire.
Do not overload the tires by exceeding the
specified load limit. The maximum permissi-
ble load can be found on the vehicle's Tire and Loading Information placard on the B-pillar onthe driver's side (Y page 412).
Example:
Load-bearing index 91 indicates a maximum
load of 1,356 lb (615 kg) that the tires can
bear. For further information on the maximum
tire load in kilograms and lbs, see
(Y page 419).
For further information on the load bearing
index, see "Load index" (Y page 419).
Speed rating: speed rating0084specifies the
approved maximum speed of the tire.
i Tire data is vehicle-specific and may devi-
ate from the data in the example.
Regardless of the speed rating, always
observe the speed limits. Drive carefully and
adapt your driving style to the traffic condi-
tions.
Summer tires Index Speed rating
Q up to 100 mph (160 km/h)
R up to 106 mph (170 km/h) Index Speed rating
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)
ZR...(..Y) over 186 mph (300 km/h)
ZR over 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 ZR18).
The service specification is made up of
load-bearing index 0083and speed rating 0084.
R If the size description of your tire includes
"ZR" and there are no service specifica-
tions, 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 ZR18 97 Y.In this exam-
ple, "97 Y" is the service specification. The letter "Y" represents the speed rating. The
maximum speed of the tire is limited to
186 mph (300 km/h).
R The size description for all tires with maxi-
mum speeds of over 186 mph (300 km/h)
must include "ZR", andthe service specifi-
cation must be given in parentheses. Exam- ple: 275/40 ZR 18 (99 Y). Speed rating
"(Y)" indicates that the maximum speed of
the tire is over 186 mph (300 km/h). Ask
the tire manufacturer about the maximum
speed. 418
All about wheels and tiresWheels and tires

ble load can be found on the vehicle's Tire and
Loading Information placard on the B-pillar on
the driver's side (Y page 412).
i The actual values for tires are vehicle-
specific and may deviate from the values in
the illustration.
DOT, Tire Identification Number (TIN) U.S. tire regulations prescribe that every tire
manufacturer or retreader must imprint a TIN
in or on the sidewall of every tire produced. The TIN is a unique identification number. The
TIN enables the tire manufacturers or retread- ers to inform purchasers of recalls and other
safety-relevant matters. It makes it possible
for the purchaser to easily identify the affec-
ted tires.
The TIN is made up of manufacturer identifi-
cation code 0044, tire size0087, tire type code 0085
and manufacturing date 0083.
DOT (Department of Transportation): tire
symbol 0043indicates that the tire complies
with the requirements of the U.S. Department
of Transportation.
Manufacturer identification code: manu-
facturer identification code 0044provides
details on the tire manufacturer. New tires
have a code with two symbols. Retreaded
tires have a code with four symbols.
For further information about retreaded tires,
see (Y page 428).
Tire size: identifier0087describes the tire size. Tire type code:
tire type code0085can be used
by the manufacturer as a code to describe
specific characteristics of the tire.
Date of manufacture: date of manufacture
0083 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.
i Tire data is vehicle-specific and may devi-
ate from the data in the example.
Tire characteristics This information describes the type of tire
cord and the number of layers in sidewall
0043
and under tire tread 0044.
i Tire data is vehicle-specific and may devi-
ate from the data in the example.
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. 14.5038 pounds
per square inch (psi) and 100 kilopascals
(kPa) are the equivalent of 1 bar. 420
All about wheels and tiresWheels and tires

the tire. This specifies the load-bearing capa-
city more precisely.
Curb weight
The weight of a vehicle with standard equip-
ment including the maximum capacity of fuel,
oil and coolant. It also includes the air-condi- tioning system and optional equipment if
these are installed in the vehicle, but does notinclude passengers or luggage.
Maximum load rating
The maximum tire load is the maximum per-
missible weight in kilograms or lbs for which a
tire is approved.
Maximum permissible tire pressure
Maximum permissible tire pressure for one
tire.
Maximum load on one tire
Maximum load on one tire. This is calculated
by dividing the maximum axle load of one axle
by two.
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
outward force to each square inch of the tire's surface. 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:
R if the vehicle has been parked without
direct sunlight on the tires for at least three
hours and
R if the vehicle has been driven for less 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 from the 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 kilograms (5 lbs).
These optional extras, such as high-perform-
ance brakes, level control, a roof rack or a
high-performance battery, are not included in the curb weight and the weight of the acces-
sories.
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 purchasers. The TIN is made up of the
manufacturer'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 capacity of a tire.
Traction
Traction is the result of friction between the
tires and the road surface.
TWR (Tongue Weight Rating)
The TWR specifies the maximum permissible
weight that the ball coupling of the trailer tow
hitch can support. 422
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wheels and tiresWheels and tires