0046Uniform Quality Grading Standards
( Y page 124)0047DOT, Tire Identification Number (TIN)
( Y page 129)008AMaximum tire load ( Y page 122)0088Maximum tire inflation pressure
( Y page 119)0086Manufacturer0087Tire ply material ( Y page 130)006ETire size designation, load and speed
rating ( Y page 126)006FLoad identification ( Y page 128)0070Tire 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 202).
Tire size designation, load and speed
rating0046Tire width0047Aspect ratio in %008ARadial tire code0088Rim diameter0086Tire load rating0087Tire speed rating
i For information 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.
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Tire width
Tire width 0046 indicates the nominal tire
width in mm.
Aspect ratio
Aspect ratio 0047 is the dimensional
relationship between tire section height
and section width and is expressed as a
percentage. The aspect ratio is arrived at
by dividing section height by section
width.
Tire code
Tire code 008A 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 127).
Rim diameter
Rim diameter 0088 is the diameter of the
bead seat, not the diameter of the rim edge.
Rim diameter is indicated in inches (in).
Tire load ratingGWarning!
The tire load rating must always be at least
half of the GAWR of your vehicle. Otherwise,
tire failure may result and cause an
accident and/or serious personal 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.
Tire load rating 0086 is a numerical code
associated with the maximum load a tire
can support.
For example, a load rating of 91
corresponds to a maximum load of 1 356 lbs
(615 kg) the tire is designed to support.
See also “Maximum tire load” ( Y page 122)
where the maximum load associated with
the load index is indicated in kilograms
and lbs.
For additional information on tire load
rating, see “Load identification”
( Y page 128).
Tire speed rating GWarning!
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
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.
Tire speed rating 0087 indicates the
approved maximum speed for the tire.
Summer tires
IndexSpeed ratingQup 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)Tires and wheels127>> Operation.451_AKB; 3; 22, en-USd2ureepe,Version: 2.11.8.12009-07-27T09:36:34+02:00 - Seite 127Z
IndexSpeed ratingHup 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...Yabove 186 mph (300 km/h)ZR...(Y)above 186 mph (300 km/h)ZRabove 149 mph (240 km/h)
RAt 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
tire load rating 0086 and tire speed rating
0087 .
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 rating
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 tiresIndexSpeed ratingQ M+S 15up to 100 mph (160 km/h)T M+S15up to 118 mph (190 km/h)H M+S 15up to 130 mph (210 km/h)V M+S15up to 149 mph (240 km/h)
i
Not all M+S rated tires provide special
winter performance. Make sure the tires
you use show M+S and the mountain/
snowflake marking 004D 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.
Load identification
i For illustration purposes only. Actual
data on tires are specific to each vehicle
and may vary from data shown in above
illustration.
15 or M+S 004D for winter tires.128Tires and wheels>> Operation.
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In addition to the tire load rating, special
load identification 0046 may be molded into
the tire sidewall following the letter
designating the tire speed rating 0087
( Y page 127).
No specification given: absence of any text
(like in above example) indicates a
standard load (SL) tire.
XL or Extra Load: designates an extra load
(or reinforced) tire.
Light Load: designates a light load tire.
C, 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.
The TIN is a unique identifier which
facilitates efforts by tire manufactures 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” 0047, “Tire size” 008A,
“Tire type code” 0088, and “Date of
manufacture” 0086.
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 0046 which denotes the
tire meets requirements of the U.S.
Department of Transportation.
Manufacturer’s identification mark
Manufacturer’s identification mark 0047
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 ( Y page 114).
Tire size
Code 008A indicates the tire size.
Tire type code
Tire type code 0088 may, at the option of the
manufacturer, be used as a descriptive
code for identifying significant
characteristics of the tire.
Date of manufacture
Date of manufacture 0086 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, “3202” represents the 32nd
week of 2002.
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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. It is indicated
on certification label located on the
driver’s door B‑pillar.
Kilopascal (kPa)
The metric unit for air pressure. There are
6.9 kPa to 1 psi; another metric unit for air
pressure is bars. There are
100 kilopascals (kPa) to 1 bar.
Maximum load rating
The maximum load in kilograms and pounds
that can be carried by the tire.
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 lbs).
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 driver’s door B‑pillar and
provides best handling, tread life and
riding comfort.
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 load rating
Numerical code associated with the
maximum load a tire can support.
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effectiveness of the ABS and ESP®
in winter
operation.
For safe handling, make sure all mounted
winter tires are of the same make and have
the same tread design.
For information on winter tires for your
vehicle model, see the "Technical data"
section ( Y page 202).
Always observe the speed rating of the
winter tires installed on your vehicle. If
the maximum speed for which your tires are
rated is below the speed rating of your
vehicle, you must place a notice to this
effect where it will be seen by the driver.
Such notices are available at your tire
dealer or any authorized smart center.
Snow chains*
! Remember that snow chains must always
be compatible with the tire sizes of a
vehicle. Snow chains that are approved
by smart are only permitted for the
following tire size:
175/55 R15 on the rear axle.
For safety reasons, smart recommends
that you only use snow chains that have
been approved by smart.
Information on this is available from any
smart center.
Please refer to the separate operating
instructions for detailed information on
mounting the snow chains.
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.
Please observe the following guidelines
when using snow chains:
R Using snow chains is not permissible
with all wheel/tire combinations
( Y page 202).
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 Use of snow chains may be prohibited
depending on location. Always check
local and state laws before mounting
snow chains.GWarning!
When mounting or removing snow chains,
always park your vehicle on level ground,
engage the parking brake, and turn off the
engine. The vehicle could otherwise move
and injure yourself or other road users.
GWarning!
When mounting and removing snow chains,
ensure that you and your vehicle are at a
safe distance from moving traffic. Not
doing so could endanger other road users or
even lead to you being injured by the
vehicles behind you.
GWarning!
The vehicle’s handling changes when
driving with snow chains on any kind of
road surface. This means that you should
always adapt your driving style to suit the
current road and weather conditions.
! If snow chains that do not meet
requirements are mounted, they may
scrape against the body or axle
components when the vehicle is in
motion. This could result in damage to
the rim/tire or vehicle.
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smart recommends winter tires
( Y page 132) 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 for an
extended period when driving off on
slippery road surfaces. Otherwise, the
drivetrain could be damaged, which is
not covered by the smart Limited
Warranty.
Tire speed rating
Regardless of the tire speed rating, local
speed limits should be obeyed. Use prudent
driving speeds appropriate to prevailing
conditions.
GWarning!
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
personal injury and possible death, for you
and for others.
An electronic speed limiter prevents your
vehicle from exceeding a speed of 90 mph
(145 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 202), for example when purchasing
new tires.
For information on how to identify the tire
speed rating on a tire’s sidewall, see “Tire
size designation, load and speed rating”
( Y page 126).
If you are uncertain about the correct
reading of the information given on a
tire’s sidewall, any authorized smart
center will be glad to assist you.
i For information on speed ratings for
winter tires, see “All-season and winter
tires” ( Y page 127).
Winter driving instructions
The most important rule for slippery or icy
roads is to drive sensibly and to avoid
abrupt acceleration, braking and steering
maneuvers.
When the vehicle is in danger of skidding,
move gear selector lever to neutral
position N. Try to keep the vehicle under
control by corrective steering action.
For information on driving with snow
chains*, see “Snow chains*” ( Y page 133).
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.
Road salts and chemicals can adversely
affect braking efficiency. Increased pedal
force may become necessary to produce the
normal braking effect.
Depressing the brake pedal periodically
when traveling at length on salt-strewn
roads can bring road-salt-impaired
braking efficiency back to normal.
If the vehicle is parked after being driven
on salt-treated roads, the braking
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Tire Pressure Monitoring System (TPMS)* ProblemPossible causes/consequences and 0050 Solutions0077The
combination
low tire
pressure/TPMS
malfunction
telltale
illuminates
continuously.The TPMS detects a loss of pressure in at least one tire.XCarefully bring the vehicle to a halt, avoiding abrupt
steering and braking maneuvers. Observe the traffic
situation around you.XCheck and correct tire inflation pressure as required
( Y page 116).
If the tire inflation pressure in the respective tire(s) has
(have) been corrected, the combination low tire pressure/TPMS
malfunction telltale goes out after a few minutes of driving.
See also “Restarting the TPMS” ( Y page 119).
0077The
combination
low tire
pressure/TPMS
malfunction
telltale flashes
60 seconds and
then stays
illuminated.There is a malfunction in the TPMS.XHave the TPMS checked at an authorized smart center.
After the malfunction has been remedied the combination low
tire pressure/TPMS malfunction telltale goes out after a few
minutes of driving.
GWarning!
Each tire should be checked monthly when cold and inflated to the inflation pressure
recommended by the vehicle manufacturer on the Tire and Loading Information placard. If
your vehicle has tires of a different size than the size indicated on the Tire and Loading
Information placard, 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
is 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.
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