Uniform Tire Quality Grading
Standards
Overview of Tire Quality Grading
Standards
Uniform Tire Quality Grading Standards are
U.S. government specifications. Their
purpose is to provide drivers with uniform
reliable information on tire performance data.
tire manufacturers have to grade tires using
three performance factors: tread wear
0002,
tire traction 0003and heat resistance 0022. All
tires sold in North America are provided with
the corresponding quality class mark on the
sidewall of the tire, even though these
regulations do not apply to Canada.
i The actual values for tires are vehicle-
specific and may deviate from the values in
the illustration.
Where applicable, the tire grading
information can be found on the tire sidewall
between the tread shoulder and maximum
tire width.
For example: Treadwear Traction Temperature
200 AA A
All passenger car tires must conform to the
statutory safety requirements in addition to
these grades. Treadwear
The treadwear grade is a comparative rating
based on the wear rate of the tire when tested
under controlled conditions on a specified
U.S. government course. For example, a tire
graded 150 would wear one and one-half
times as well on the government course as a
tire graded 100.
The relative performance of tires depends
upon the actual conditions of their use,
however, and may depart significantly from
the norm, due to variations in driving habits,
service practices and differences in road
characteristics and climat econditions. Traction
G
WARNING
The traction grade assigned to this tire is
based on straight-ahead braking traction
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 a wet surface as
measured under controlled conditions on
specified government test surfaces of asphalt
and concrete. Atire 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
conditions when temperatures are around
the freezing point.
Mercedes-Benz recommends a minimum
tread depth of 000Ain(4 mm) for all four winter
tires (Y page 302) to maintai nnormal driving
characteristics in winter. Winter tires can
reduce the braking distance on snow-covered
surfaces in comparison with summer tires.
Stopping distance, however, is still
considerably greater than when the road is 316
Uniform Tire Quality Grading StandardsWheels and tires
adapt your driving style to the traffic
conditions. Summer tires
Index Speed rating
Q up to 100 mph (160 km/h)
R up to 106 mph (170 km/h)
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 specificatio nis made up of
load-bearing index 001Fand speed rating
0020.
R If the size description of your tire includes
"ZR" and there are no service
specifications, 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 ZR 18 97 Y.In this
example, "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 descriptio nfor all tires with
maximum speeds of over 186 mph (300 km/h) must include "ZR", and
the
service specification must be given in
parentheses. Example:
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. All-weather tires and winter tires
Index Speed rating
Q M+S
7 up to 100 mph (160 km/h)
T M+S
7 up to 118 mph (190 km/h)
H M+S
7 up to 130 mph (210 km/h)
V M+S
7 up to 149 mph (240 km/h)
i
Not 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 0002snowflake symbol on
the tire wall. Tires with this marking fulfill
the requirements of the Rubber
Manufacturers Association (RMA) and the
Rubber Association of Canada (RAC)
regarding snow traction, and were specially
developed for driving on snow.
An electronic speed limiter prevents your
vehicle from exceeding the following speeds:
R all vehicles (except AMG vehicles):
130 mph (210 km/h)
R AMG vehicles: 155 mph (250 km/h)
R AMG vehicles with increased top speed:
174 mph (280 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 for your vehicle as specified in
the "tires" section (Y page 328), e.g. if you
buy new tires.
7 Or M+S0002 for winter tires. Tire labeling
319Wheels and tires Z
safety if retreaded tires are mounted. Do
not mount used tires if you have no
information aboutt heir previous usage.
i The recommended pressures for various
operating conditions can be found:
R on the Tire and Loading Information
placard with the recommended tire
pressures on the B-pillar on the driver's
side
R in the tire pressure table on the inside of
the fuel filler flap
Observe the notes on recommended tire
pressures under various operating
conditions (Y page 303).
Check tire pressures regularly, and only
when the tires are cold. Comply with the
maintenance recommendations of the tire
manufacturer in the vehicle document
wallet.
i Notes on the vehicle equipment –always
equip the vehicle with:
R tires of the same size on a given axle
(left/right)
R the same type of tires at a given time
(summer tires, winter tires, MOExtended
tires)
i On the following pages, you can find
information on approved wheel rims and
tire sizes for equipping your vehicle with
winter tires. Winter tires are not available
at the factory as standard equipmen tor
optional extras.
If you would like to equip your vehicle with
approved winter tires, you may also, in
certain circumstances, require rims of the
appropriate size. The size of the approved
winter tires may deviate from that of the
standard tires. This is dependent on the
model and the equipment installed at the
factory.
The tires and wheel rims, as well as further
information, can be obtained at a qualified
specialist workshop. i
Overview of abbreviations used in the
following tire tables:
R BA: both axles
R FA: front axle
R RA: rear axle
In the following table, the wheel/tire
combinations are assigned to the vehicle
models through variants, e.g. V1, V2 etc.: V1 C 250
V2 C 350, C 350 4MATIC
V3 C 63 AMG
i
Not all wheel and tire combinations are
available at the factory for all countries. Wheel and tire combinations
329Wheels and tires Z
All-weather tires Alloy wheels V1 V2 V3
FA
RA 225/45 R17 91 H M+S
245/40 R17 91 H M+S
10 7.5 J x 17 H2
Wheel offset: 1.85 in (47 mm)
8.5 J x 17 H2
Wheel offset: 2.28 in (58 mm) 001C
— —
FA
RA 225/40 R18 92 H XL M+S
255/35 R18 94 H XL M+S
10, 11 8.0 J x 18 H2
Wheel offset: 1.97 in (50 mm)
8.5 J x 18 H2
Wheel offset: 2.13 in (54 mm) 001C 001C
—
Winter tires Alloy wheels V1 V2 V3
BA 205/55 R16 91 H M+S0002 7.0 J x 16 H2
Wheel offset: 1.69 in (43 mm) 001C
— —
BA 225/45 R17 91 H M+S0002 7.5 J x 17 H2
Wheel offset: 1.85 in (47 mm) 001C 001C
—
BA 225/40 R18 92 V XL M+S0002 8.0 J x 18 H2
Wheel offset: 1.77 in (45 mm) — — 001C
BA
235/40 R18 95 V XL M+S0002
10 8.0 J x 18 H2
Wheel offset: 1.77 in (45 mm) — — 001C
FA
RA 235/40 R18 95 V XL M+S0002
255/35 R18 94 V XL M+S0002
10 8.0 J x 18 H2
Wheel offset: 1.77 in (45 mm)
9.0 J x 18 H2
Wheel offset: 2.13 in (54 mm) — — 001C
Emergency spare wheel
Important safety notes
G
WARNING
The wheel or tire size as well as the tire type
of the spare wheel or emergency spare wheel
and the wheel to be replace dmay differ.
Mounting an emergency spar ewheel may
severely impair the driving characteristics.
There is a risk of an accident. To avoid hazardous situations:
R
adapt your driving style accordingly and
drive carefully.
R never mount more than one spare wheel or
emergency spare wheel that differs in size.
R only use a spare wheel or emergency spare
wheel of a different size briefly.
R do not switch ESP ®
off.
R have a spare wheel or emergency spare
wheel of a different size replaced at the
nearest qualified specialist workshop.
10 Use of snow chains is not permitted. Observe the notes in the section on snow chains.
11 Additional measures necessary (hub caps on rear axle, code 776). Emergency spare wheel
331Wheels and tires
Z