Weight Rating (GVWR) and the Gross Axle
Weight Rating (GAWR) for either the front or
rear axle. You can obtain the GVWR and
GAWR from the certification label. The
certification label can be found on the driver’s
door B-pillar, see the “Technical data” section
(Y page 346).
Gross Vehicle Weight Rating (GVWR): The
total weight of the vehicle, all occupants, all
cargo, and the trailer tongue load (if
applicable) must never exceed the GVWR.
Gross Axle Weight Rating (GAWR): The total
allowable weight that can be carried by a
single axle (front or rear).
To assure that your vehicle does not exceed
the maximum permissible weight limits
(GVWR and GAWR for front and rear axle),
have the loaded vehicle (including driver,
passengers and all cargo and, if applicable,
trailer fully loaded) weighed on a suitable
commercial scale.
Trailer tongue load
The tongue load of any trailer is an important
weight to measure because it affects the load
you can carry in your vehicle. If a trailer is
towed, the tongue load must be added to the
weight of all occupants riding and any cargo
you are carrying in the vehicle. The tongue
load typically is between 8% and 15% of the
trailer weight and everything loaded in it.
Maximum tire load
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.
iFor illustration purposes only. Actual data
on tires are specific to each vehicle and
may vary from data shown in above
illustration.
The maximum tire load rating : is the
maximum weight the tires are designed to
support.
For more information on tire load rating, see
(Y page 236).
For information on calculating total and cargo
load capacities, see (Y page 228).
Direction of rotation
Unidirectional tires offer added advantages,
such as better hydroplaning performance. To
benefit, however, you must make sure the
tires rotate in the direction specified.
An arrow on the sidewall indicates the
intended direction of rotation of the tire.
Spare wheels may be mounted against the
direction of rotation (spinning) even with a
unidirectional tire for temporary use only until
the regular drive wheel has been repaired or
replaced. Always observe and follow
applicable temporary use restrictions and
speed limitations indicated on the spare
wheel.
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.
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You may only use the MOExtended system in
conjunction with the tire pressure loss
warning system ( Y page 222) or the
Advanced TPMS ( Y page 223).
i Vehicles with MOExtended system are
not factory-equipped with a TIREFIT kit.
When retrofitting with tires that do not have
run-flat characteristics, e.g. winter tires,
you should also equip your vehicle with a
TIREFIT kit. TIREFIT kits are available at any
authorized Mercedes-Benz Center.
For information on driving in case of pressure
loss in one or more tires (emergency mode),
see the “Practical hints” section
( Y page 330).
Tire care and maintenance
GWarning!
Regularly check the tires for damage.
Damaged tires can cause tire inflation
pressure loss. As a result, you could lose
control of your vehicle.
Worn, old tires can cause accidents. If the tire
tread is worn to minimum tread depth, or if
the tires have sustained damage, replace
them.
Check the tire inflation pressure at least once
a month. For more information on checking
tire inflation pressure, see “Recommended
tire inflation pressure” ( Y page 219).
Tire inspection
Every time you check the tire inflation
pressure, you should also inspect your tires
for the following:
R excessive treadwear ( Y page 232)
R cord or fabric showing through the tire’s
rubber
R bumps, bulges, cuts, cracks or splits in the
tread or side of the tire
Replace the tire if you find any of the above
conditions.
Make sure you also inspect the spare tire
periodically for condition and inflation. Spare
tires will age and become worn over time even
if never used, and thus should be inspected
and replaced when necessary.
Life of tire GWarning!
Tires and spare tire should be replaced after
6 years, regardless of the remaining tread.
The service life of a tire is dependent upon
varying factors including but not limited to:
R Driving style
R Tire inflation pressure
R Distance driven
Tread depth
GWarning!
Although the applicable federal motor vehicle
safety laws consider a tire to be worn when
the treadwear indicators (TWI) become visible
at approximately 1
/ 16 in (1.6 mm), we
recommend that you do not allow your tires
to wear down to that level. As tread depth
approaches 1
/ 8 in (3 mm), the adhesion
properties on a wet road are sharply reduced.
Depending upon the weather and/or road
surface (conditions), the tire traction varies
widely.
Do not allow your tires to wear down too far.
Adhesion properties on wet roads are sharply
reduced at tread depths of less than 1
/ 8 in
(3 mm).
Treadwear indicators (TWI) are required by
law. These indicators are located in six places
on the tread circumference and become
visible at a tread depth of approximately
1 / 16 in (1.6 mm), at which point the tire is
considered worn and should be replaced.
The recommended minimum tire tread depth
for summer tires is 1
/ 8 in (3 mm). The
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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 233)
;DOT, Tire Identification Number
(Y page 238)
=Maximum tire load (Y page 231)?Maximum tire inflation pressure
(Y page 226)
AManufacturerBTire ply material (Y page 239)CTire size designation, load and speed
rating (Y page 236)
DLoad identification (Y page 238)ETire name
iFor 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 352).
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Tire size designation, load and speed
rating:Tire width;Aspect ratio in %=Radial tire code?Rim diameterALoad index BSpeed symbol
iFor 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 237).
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
GWarning!
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.
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.
Load index A is a numerical code associated
with the maximum load a tire can support.
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IndexSpeed ratingH M+S20up to 130 mph (210 km/h)V M+S20up to 149 mph (240 km/h)
iNot all M+S rated tires provide special
winter performance. Make sure the tires
you use show M+S and the mountain/
snowflakeimarking on the tire
sidewall. These tires meet specific snow
traction performance requirements of the
Rubber Manufacturers Association (RMA)
and the Rubber Association of Canada
(RAC) and have been designed specifically
for use in snow conditions.
An electronic speed limiter prevents your
vehicle from exceeding a speed of:
RAll models except ML 63 AMG:
130 mph (210 km/h)
RML 63 AMG:
155 mph (250 km/h)
RML 63 AMG with increased top speed:
171 mph (275 km/h)
The factory equipped tires on your vehicle
may have a tire speed rating above the
maximum speed permitted by the electronic
speed limiter.
Make sure your tires have the required tire
speed rating as specified for your vehicle in
the “Technical data” section (Y page 352),
for example when purchasing new tires.
If you are uncertain about the correct reading
of the information given on a tire’s sidewall,
any authorized Mercedes-Benz Center will be
glad to assist you.
Load identification
iFor illustration purposes only. Actual data
on tires are specific to each vehicle and
may vary from data shown in above
illustration.
In addition to the load index, special load
identification : may be molded into the tire
sidewall following the letter designating the
speed symbol B (Y page 236).
RNo specification given: absence of any text
(like in above example) indicates a
standard load (SL) tire.
RXL or Extra Load: designates an extra load
(or reinforced) tire.
RLight Load: designates a light load tire.
RC, D, E: designates load range associated
with the maximum load a tire can carry at
a specified pressure.
DOT, Tire Identification Number (TIN)
U.S. tire regulations require each new tire
manufacturer or tire retreader to mold a TIN
into or onto a sidewall of each tire produced.
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radio, and heater, to the extent that these
items are available as factory-installed
equipment (whether installed or not).
Air pressure
The amount of air inside the tire pressing
outward on each square inch of the tire. Air
pressure is expressed in pounds per square
inch (psi), kilopascal (kPa), or bar.
Aspect ratio
Dimensional relationship between tire
section height and section width expressed
in percentage.
Bar
Metric unit for air pressure. There are
14.5038 pounds per square inch (psi) to
1 bar; there are 100 kilopascals (kPa) to 1 bar.
Bead
The tire bead contains steel wires wrapped by
steel cords that hold the tire onto the rim.
Cold tire inflation pressure
Tire inflation pressure when your vehicle has
been sitting for at least 3 hours or driven no
more than 1 mile (1.6 km).
Curb weight
The weight of a motor vehicle with standard
equipment including the maximum capacity
of fuel, oil, and coolant, and, if so equipped,
air conditioning and additional optional
equipment, but without passengers and
cargo.
DOT (Department of Transportation)
A tire branding symbol which denotes the tire
meets requirements of the U.S. Department
of Transportation.
GAWR (Gross Axle Weight Rating)
The GAWR is the maximum permissible axle
weight. The gross vehicle weight on each axle
must never exceed the GAWR for the front
and rear axle indicated on the certification
label located on the driver’s door B-pillar.
GTW (Gross Trailer Weight)
The GTW is the weight of the trailer plus the
weight of all cargo, equipment, luggage etc.
loaded on the trailer.
GVW (Gross Vehicle Weight)
The GVW comprises the weight of the vehicle
including fuel, tools, spare wheel, installed
accessories, passengers and cargo and, if
applicable, trailer tongue load. The GVW must
never exceed the GVWR indicated on the
certification label located on the driver’s door
B-pillar.
GVWR (Gross Vehicle Weight Rating)
This is the maximum permissible vehicle
weight of the fully loaded vehicle (weight of
the vehicle including all options, passengers,
fuel, and cargo and, if applicable, trailer
tongue load). It is indicated on the
certification label located on the driver’s door
B-pillar.
Kilopascal (kPa)
Metric unit for air pressure. There are 6.9 kPa
to 1 psi; another metric unit for air pressure
is bar. There are 100 kilopascals (kPa) to
1 bar.
Load index
Numerical code associated with the
maximum load a tire can support.
Maximum load rating
The maximum load in kilograms and pounds
that can be carried by the tire.
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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.
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After installing winter tires:XCheck the tire inflation pressure and adjust
it if necessary ( Y page 221).XRestart the tire pressure loss warning
system ( Y page 222) or the Advanced Tire
Pressure Monitoring System (Y page 223).
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 352).
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 63)
before setting the vehicle in motion. This
will improve the vehicle’s traction.
Winter driving instructions
GWarning!
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.
GWarning!
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.
GWarning!
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
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