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Radio type approval for the tire pres-
sure monitor
CountryRadio type approval number
USAFCC ID: MRXMW2433A
FCC ID: MRXGG4
FCC ID: MRXMC34MA4
CanadaIC: 2546A-MW2433A
IC: 2546A-GG4
IC: 2546A-MC34MA4
Loading the vehicle
Instruction labels for tires and loads
GWARNING
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 occu-
pants 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 iden-
tification 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 infor-
mation 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
a
xle weight rating for the front or rear axle.
:B-pillar, driver's side
Maximum permissible gross vehicle
weight rating
XSpecification for maximum gross vehicle
weight :is 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 specified
value.
iThe 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.
Loading the vehicle311
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Page 314 of 338

Number of seats
Maximum number of seats:indicates the
maximum number of occupants allowed to
travel in the vehicle. This information can be
found on the Tire and Loading Information plac-
ard.
iThe specifications shown on the Tire and
Loading Information placard in the illustration
are examples. The number of seats is vehicle-
specific and can differ from the details shown.
The number of seats in your vehicle can be
found on the Tire and Loading Information
placard.
Determining the correct load limit
Step-by-step instructions
The following steps have been developed as
required of all manufacturers under Title 49, Code of U.S. Federal Regulations, Part 575 pur-
suant to the "National Traffic and Motor Vehicle
Safety Act of 1966".
XStep 1: Locate the statement "The combined
weight of occupants and cargo should never
exceed XXX kg or XXX lbs." on your vehicle's
Tire and Loading Information placard.
XStep 2: Determine the combined weight of
the driver and passengers that will be riding in your vehicle.
XStep 3: Subtract the combined weight of the
driver and passengers from XXX kilograms or
XXX lbs.
XStep 4: The resulting figure equals the avail-
able amount of cargo and luggage load capa-
city. For example, if the "XXX" amount equals
1400 lbs and there will be five 150-lb pas-
sengers in your vehicle, the amount of avail-
able cargo and luggage load capacity is
650 lbs (1400 - 750 (5 x 150) = 650 lbs).
XStep 5: Determine the combined weight of
luggage and cargo being loaded on the vehi-
cle. That weight may not safely exceed the
available cargo and luggage load capacity cal- culated in step 4.
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 use a load limit of
1500 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 Information placard (
Ypage 311).
The greater the combined weight of the occupants, the lower the maximum luggage load.
Example 1
Step 1
RCombined maximum weight of occupants and load (data from the Tire and Loading Information
placard): 1500 lbs (680kg )
31 2Loading the vehicle
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Step 2
RNumber of people in the vehicle (driver and occupants): 5
RDistribution of the occupants
-Front: 2
-Rear: 3
RWeight of the occupants
-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)
RTotal weight of all occupants: 750 lbs (340 kg)
Step 3
RPermissible load (maximum gross vehicle weight rating from the Tire and Loading Information
placard minus the gross weight of all occupants):
1500 lbs (680 kg) Ò750 lbs (340 kg) = 750 lbs (340 kg)
Example 2
Step 1
RCombined maximum weight of occupants and load (data from the Tire and Loading Information
placard): 1500 lbs (680 kg)
Step 2
RNumber of people in the vehicle (driver and occupants): 3
RDistribution of the occupants
-Front: 1
-Rear: 2
RWeight of the occupants
-Occupant 1: 200 lbs (91 kg)
-Occupant 2: 190 lbs (86 kg)
-Occupant 3: 150 lbs (68 kg)
RTotal weight of all occupants: 540 lbs (245 kg)
Step 3
RPermissible load (maximum gross vehicle weight rating from the Tire and Loading Information
placard minus the gross weight of all occupants):
1500 lbs (680 kg) Ò540 lbs (245 kg) =960 lbs (435 kg)
Example 3
Ste
p 1
RCombined maximum weight of occupants and load (data from the Tire and Loading Information
placard): 1500 lbs (680 kg)
Step 2
RNumber of people in the vehicle (driver and occupants): 2
RDistribution of the occupants:
-Front: 1
RWeight of the occupants
-Occupant 1: 150 lbs (68 kg)
RTotal weight of all occupants: 150 lbs (68 kg)
Loading the vehicle313
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Step 3
RPermissible load (maximum gross vehicle weight rating from the Tire and Loading Information
placard minus the gross weight of all occupants):
1500 lbs (680 kg)Ò150 lbs (68 kg) = 1350 lbs (612kg )
Vehi cle identification plate
Even if you have calculated th etotal cargo care-
fully, you should still mak esure that th egross
vehicl eweigh trating and th egross axle weigh t
rating are no texceeded. Details can be foun don
th evehicl eidentification plat eon th eB-pillar on
th edriver' sside of th evehicl e (
Ypage 311).
Permissible Gross Vehicle Weight Ratin g
(GVWR): thegross weigh tof th evehicle, all pas-
sengers, load and trailer load/noseweight (if
applicable) must no texcee dth epermissible
gross vehicl eweight.
Gross Axle Weight Ratin g(GAWR): themaxi-
mum permissible load that can be carried by on e
axle (fron tor rear axle).
To ensure that your vehicl edoes no texcee dth e
maximum permissible value s(gross vehicl e
weigh tand maximum gross axle weigh trating),
have your loade dvehicl e(including driver, occu-
pants ,cargo, and full trailer load if applicable)
weighed on asuitable vehicl eweighbridge.
All about wheels and tires
Uniform Tire Quality Grading Stand-
ards
Overview of Tire Quality Grading Stand-
ards
Uniform Tir eQuality Grading Standards are U.S.
governmen tspecifications. Thei rpurpose is to
provide drivers wit huniform reliable information
on tir eperformance data. Tir emanufacturers have to grad
etires usin gthree performance fac -
to rs: : tread wear grade, ;traction grad eand
= temperature grade. Thes eregulation sdo no t
apply to Canada. Nevertheless, all tires sold in
North Americ aare provide dwit hth ecorre-
spondin gqualit ygrading markings on th eside -
wall of th etire.
Quality grades can be found, wher eapplicable,
on th etir esidewall between tread shoulder and
maximum sectio nwidth.
Example :
RTreadwear grade: 200
RTraction grade: AA
RTemperaturegrade: A
All passenger car tires must conform to th estat-
utory safet yrequirements in addition to these
grades.
iThe actual value sfor tires are vehicle-spe-
cific and may deviat efrom th evalue sin th e
illustration .
Treadwear
The treadwear grad eis acomparative rating
based on th ewear rat eof th etir ewhen tested
under controlled condition son aspecifie dU.S.
governmen tcourse .Fo rexample , atiregraded
15 0would wear on eand one-half times as well
on th egovernmen ttest track as atir egraded
100.
The relative performance of tires depend supon
th eactual condition sof their use, however ,and
may depar tsignificantly from th enorm due to
variation sin driving habits, servic epractices
and differences in road characteristics and cli -
mate.
Traction
GWARNIN G
The traction grad eassigned to this tir eis
based on straight-ahead braking traction
tests, and does no tinclude acceleration ,cor-
nering, hydroplaning ,or peak traction char-
acteristics.
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!Avoid wheelspin. This can lead to damage to
the drive train.
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 meas-
ured under controlled conditions on specified
government test surfaces of asphalt and con-
crete. A tire marked C may have poor traction
performance.
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 condi-
tions when temperatures are around freezing
point.
Mercedes-Benz recommends a minimum tread
depth of ãin (4 mm) on all four winter tires.
Observe the legally required minimum tire tread
depth (
Ypage 303). Winter tires can reduce the
braking distance on snow-covered surfaces in
comparison with summer tires. The braking dis-
tance is still much further than on surfaces that
are not icy or covered with snow. Take appro-
priate care when driving.
Further information on winter tires (M+S tires)
(
Ypage 304).
Temperature
GWARNING
The temperature grade for this tire is estab-
lished for a tire that is properly inflated and
not overloaded. Excessive speed, underinfla-
tion, 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. Sus-
tained 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
Overview
:Uniform Tire Quality Grading Standard
(Ypage 318)
;DOT, Tire Identification Number
(Ypage 318)
=Maximum tire load (Ypage 317)
?Maximum tire pressure (Ypage 307)
AManufacturer
BTire material (Ypage 318)
CTire size designation, load-bearing capacity
and speed rating (Ypage 315)
DLoad index (Ypage 317)
ETire name
The markings described above are on the tire in
addition to the tire name (sales designation) and
the manufacturer's name.
iTire data is vehicle-specific and may deviate
from the data in the example.
Tire size designation, load-bearing
capacity and speed rating
GWARNING
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
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tire load rating and speed rating required for
your vehicle.
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. man-
ufacturing standards.
If "LT" precedes the size description: these are
light truck tires according to U.S. manufacturing
standards.
If "T" precedes the size description: compact
emergency wheels with high tire pressure that
are only designed for temporary use in an emer- gency.
Tire width: tire width:shows the nominal tire
width in millimeters.
Height-width ratio: aspect ratio;is the size
ratio between the tire height and tire width and
is shown in percent. The aspect ratio is calcula-
ted by dividing the tire width by the tire height.
Tire code:tire code =specifies the tire type.
"R" represents radial tires; "D" represents diag- onal tires; "B" represents diagonal radial tires.
Optionally, tires with a maximum speed of over
149 mph (240 km/h ) ma
y 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 indexAis a
numerical code that specifies the maximum
load-bearing capacity of a tire.
Do not overload the tires by exceeding the
specified load limit. The maximum permissible
load can be found on the vehicle's Tire and
Loading Information placard on the B-pillar on
the driver's side (
Ypage 311).
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 (
Ypage 317).
For further information on the load bearing
index, see "Load index" (
Ypage 317).
Speed rating: speed ratingBspecifies the
approved maximum speed of the tire.
iTire data is vehicle-specific and may deviate
from the data in the example.
Regardless of the speed rating, always observe
the speed limits. Drive carefully and adapt your
driving style to th
e traffic conditions.
Summer tires
IndexSpeed rating
Qup 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)
ZR...(..Y)over 186 mph (300 km/h)
ZRover 149 mph (240 km/h)
ROptionally, 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 ZR18).
The service specification is made up of load-
bearing index Aand speed rating B.
RIf the size description of your tire includes
"ZR" and there are no service specifications,
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Wheels and tires
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ask the tire manufacturer in order to find out
the maximum speed.
If a service specification is available, the max-
imum speed is limited according to the speed
rating in the service specification. Example:
245/40 ZR18 97 Y. In this example, "97 Y" is
the service specification. The letter "Y" rep-
resents the speed rating. The maximum
speed of the tire is limited to 186 mph
(300 km/h).
RThe size description for all tires with maxi-
mum speeds of over 186 mph (300 km/h)
must include "ZR",andthe service specifica-
tion must be given in parentheses. Example:
275/40 ZR 18 (99 Y). Speed rating "(Y)" indi-
cates that the maximum speed of the tire is
over 186 mph (300 km/h). Ask the tire man-
ufacturer about the maximum speed.
All-weather tires and winter tires
IndexSpeed rating
Q M+S1up to 100 mph (160 km/h)
T M+S1up to 118 mph (190 km/h)
H M+S1up to 130 mph (210 km/h)
V M+S1up to 149 mph (240 km/h)
iNot all tires with the M+S marking provide
the driving characteristics of winter tires. In
addition to the M+S marking, winter tires also
have the isnowflake symbol on the tire
wall. Tires with this marking fulfill the require-
ments of the Rubber Manufacturers Associa-
tion (RMA) and the Rubber Association of
Canada (RAC) regarding the tire traction on
snow. They have been especially developed
for driving on snow.
An electronic speed limiter prevents your vehi-
cle from exceeding a speed of 130 mph
(210 km/h).
The speed rating of tires mounted at the factory
may be higher than the maximum speed that the
electronic speed limiter permits.
Make sure that your tires have the required
speed rating, e.g. when buying new tires. The
required speed rating for your vehicle can be
found in the "Tires" section (
Ypage 325). Further information about reading tire data can
be obtained from any qualified specialist work-
shop.
Load index
In addition to the load-bearing index, load
index
:may also be imprinted on the sidewall
of the tire. You will find this after the letter that
identifies the speed rating (
Ypage 315).
RIf no specification is given: no text (as in the
example above), represents a standard load
(SL) tire
RXL or Extra Load: represents a reinforced tire
RLight Load: represents a light load tire
RC, D, E: represents a load range that depends
on the maximum load that the tire can carry at
a certain pressure
iTire data is vehicle-specific and may deviate
from the data in the example.
Maximum load rating
Maximum tire load :is the maximum permis-
sible weight for which the tire is approved.
Do not overload the tires by exceeding the
specified load limit. The maximum permissible
1Or M+S ifor winter tires.
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load can be found on the vehicle's Tire and
Loading Information placard on the B-pillar on
the driver's side (
Ypage 311).
iThe actual values for tires are vehicle-spe-
cific and may deviate from the values in the
illustration.
DOT, Tire Identification Number (TIN)
US tire regulations stipulate that every tire man-
ufacturer or retreader must imprint a TIN in or on
the sidewall of each tire produced.
The TIN is a unique identification number. The
TIN enables the tire manufacturers or retreaders
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 identifica-
tion code ;, tire size =, tire type code ?and
manufacturing date A.
DOT (Department of Transportation): tire
symbol :marks that the tire complies with the
requirements of the U.S. Department of Trans-
portation.
Manufacturer identification code: manufac-
turer identification code ;provides 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 (
Ypage 325).
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 manufactureA
provides information about the age of a tire. The
first and second positions represent the week of
manufacture, starting with "01" for the first cal-
endar 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.
iTire data is vehicle-specific and may deviate
from the data in the example.
Tire characteristics
This information describes the type of tire cord
and the number of layers in sidewall :and
under tire tread ;.
iTire data is vehicle-specific and may deviate
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.
DOT (Department of Transportation)
DOT-marked tires fulfill the requirements of the
U S Department of Transportation.
Normal occupant weight
The number of occupants for which the vehicle
is designed multiplied by 68 kilograms (150 lbs).
Uniform Tire Quality Grading Standards
A uniform standard to grade the quality of tires
with regards to tread quality, tire traction and
temperature characteristics. The quality grad-
ing assessment is made by the manufacturer
318All about wheels and tires
Wheels and tires