tire size MERCEDES-BENZ C-Class COUPE 2017 CL205 User Guide

tire load rating and speedrating required for
your vehicle.
:Tire width
;Nomina laspec tratio in %
=Tire code
?Rimd iame ter
ALoadbeari ng index
BSpeed rating
General: depending on the manufacturer's
standards ,the size imprinted in the tire wall may
not contain any letters or mayc ontain one letter
thatp recedes the size description.
If there is no letter preceding the size descrip-
tio n(as shown above): these ar epassenger
vehicl etiresa ccording to Europea nmanufac-
turing standards.
If "P "precedes the size description: these are
passenge rvehicl etiresa ccording to U.S. man-
ufacturin gstandards.
If "LT" precedes the size description: these are
light truck tire saccording to U.S. manufacturing
standards.
If "T "precedes the size description: compact
emergency wheels with high tire pressure that
ar eo nlyd esig nedf or temporary us einanemer-
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=specifie sthe tire type.
"R "r epresents radial tires; "D" represents diag-
ona ltires
; "B" represents diagona
lradial tires.
Optionally ,tire sw itham aximum spee dofover
149 mph (24 0km/h )mayhave "ZR" in the size description, depending on the manufacturer
(e.g. 245/40Z
R18).
Rim diameter: rim diameter?is the diameter
of the bead seat, not the diamete rofthe rim
flange .The ri mdiame teriss pecifie din
inches (in).
Load-bearin gind ex: load-bearing index Ais a
numerical cod ethats pecifie sthe maximum
load-bearing capacity of atire.
Do not overload the tire sbyexceeding the
specifie dloa dlimit .The maximu mpermissible
load can be found on the vehicle's Tire and
Loading Informatio nplacard on the B-pillar on
the driver's side (
Ypage 326).
Example:
Load-bearin gindex 91 indicates amaximum
load of 1,356 lb (61 5kg)thatt he tire scan bear.
For furthe rinformation on the maximum tire
load in kilograms and lbs, see(
Ypage 332).
For furthe rinformation on the load bearing
index, see" Loadindex" (
Ypage 332).
Speed rating: speedrating Bspecifie sthe
approved maximum spee dofthe tire.
iTire data is vehicle-specific and mayd eviate
fromt he data in the example.
Regardles softhe spee drating ,alway sobser ve
th

e spee dlimit s. Drive carefull yand adap tyou r
drivin gstyle to the trafficc onditions.
Summe rtires
IndexSpeed rating
Qup to 100 mph (16 0km/h)
Rup to 106 mph (17 0km/h)
Sup to 112 mph (18 0km/h)
Tup to 118 mph (19 0km/h)
Hup to 130 mph (21 0km/h)
Vup to 149 mph (24 0km/h)
Wup to 168 mph (27 0km/h)
Yup to 186 mph (30 0km/h)
ZR...Yup to 186 mph (30 0km/h)
ZR...(..Y)ove r186 mph (300 km/h)
ZRove r149 mph (240 km/h)
ROptionally ,tire sw itham aximum spee dof
ove r149 mph (24 0km/h )mayhave "ZR" in
Alla bout wheels an dtires331
Wheel sand tires
Z

the size description, depending on the man-
ufacturer (e.g. 245/40ZR18).
The service specification is made up of load-
bearing index Aand spee drating B.
RIf the size description of your tire includes
"ZR" and there ar enoservice specifications,
as kt he tire manufacturer in order to fin dout
the maximum speed.
If as ervice specification is available, the max-
imum spee dislimited according to the speed
rating in the service specification. Example:
245/40Z R1897Y.Int his 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 descriptionf or all tires with maxi-
mum speedsofo ver 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 abou tthe maximum speed.
All-weather tires and winter tires
IndexSpeed rating
QM +S1up to 100 mph (160 km/h)
TM+S1up to 118 mph (190 km/h)
HM +S1up to 130 mph (210 km/h)
VM+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 symbo lonthe 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 you rvehi-
cle from exceeding aspeed 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 you
rtires have the required
speed rating, e.g. when buying new tires. The
required speed rating for you rvehicle can be
found in the "Tires" section (
Ypage 340).
Further information abou treading tire data can
be obtained from any qualifieds pecialist work-
shop.
Load index
In addition to the load-bearing index, load
index :may also be imprinted on the sidewall
of the tire. You wil lfind this after the letter that
identifiest he speed rating (
Ypage 330).
RIf no specification is given: no text (as in the
example above), represents astandard load
(SL) tire
RXL or ExtraL oad: represents areinforced tire
RLight Load: represents alightl oad tire
RC, D, E: represents aload range that depends
on the maximum load that the tire can carry at
ac ertain pressure
iTire data is vehicle-specific and may deviate
from the data in the example.
Maximum load rating
1Or M+S ifor winter tires.
332Allabout wheels and tires
Wheelsa nd tires

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
load can be found on the vehicle's Tire and
Loading Information placard on the B-pillar on
the driver's side (
Ypage 326).
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 aTIN in or on
the sidewall of each tire produced.
The TIN is aunique 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. DepartmentofT rans-
portation.
Manufacturer identification code: manufac-
turer identification code ;provides details on
the tire manufacturer. New tires have acode
with two symbols. Retreaded tires have acode
with four symbols.
For further information about retreaded tires,
see (
Ypage 340).
Tire size: identifier=describes the tire size.
Tire type code: tire type code?can be used by
the manufacturer as acode to describe specific
characteristics of the tire. Date of manufacture:
date of manufactureA
provides information about the age of atire. The
first and second positions represent the week of
manufacture, startin gwith "01" for the first cal-
endar week. Positions three and four represent
the year of manufacture. For example, atire 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 termsf or 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 of1bar.
DOT (Department of Transportation)
DOT-marked tires fulfill the requirements of the
USD epartmen tofTransportation.
Normal occupant weight
The number of occupants for which the vehicle
is designed multiplied by 68 kilograms (150 lbs).
All about wheels and tires333
Wheels and tires
Z

PSI (pounds per squareinch)
Astandard 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 out-
ward force to each square inch of the tire's sur-
face. 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:
Rif the vehicle has been parked with the tires
out of direct sunlight for at least three hours
and
Rif the vehicle has not been driven further than
1m ile (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 5lbs (2.3 kg). These
optional extras, such as high-performance
brakes, level control, aroof rack or ahigh-per-
formanceb attery, are not included in the curb
weight and the weight of the accessories.
TIN (Tire Identification Number)
This is aunique identifier which can be used by
at ire manufacturer to identify tires, for example
for aproduct recall, and thus identify the pur-
chasers. The TIN is made up of the manufactur-
er's identity code, tire size, tire type code and
the manufacturing date.
Load bearing index
The load bearing index (also load index) is acode
that contains the maximum load bearing capa-
city of atire.
Traction
Traction is the result of friction between the tires
and the road surface.
Treadwear indicators
Narrow bars (tread wear bars) that are distrib-
uted over the tire tread. If the tire tread is level
with the bars, the wear limit of áin (1.6 mm)
has been reached.
Occupant distribution
The distribution of occupants in avehicle at their
designated seating positions.
Total load limit
Nominal load and luggage load plus 68 kg
(15 0lbs)m ultiplied by the number of seats in
the vehicle.
Changing awheel
Flat tire
The "Breakdown assistance" section
(Ypage 300) contains information and notes on
how to deal with aflat tire. Information on driv-
ing with MOExtended tires in the event of aflat
tire can be found under "MOExtended tires (tires
with run-flat characteristics" (
Ypage 301).
Rotating the wheels
GWARNING
Interchanging the front and rear wheels may
severely impair the driving characteristics if
the wheels or tires have different dimensions. The wheel brakes or suspension components
may also be damaged. There is arisk of acci-
dent.
Rotate front and rear wheels only if the wheels and tires are of the same dimensions.
!On vehicles equippedw ithatire pressure
monitor ,electronic components are located
in the wheel.
Changing awheel335
Wheels and tires
Z

Tire-mounting tools should not be used near
the valve. This could damage the electronic
components.
Only have tires changed ataqualified spe-
cialist workshop.
Always observe the instructions and safety
notes in the "Mounting awheel" section
(
Ypage 336).
The wear pattern sonthe front and rear tires
differ, depending on the operating conditions.
Rotate the wheels before aclear wear pattern
has formed on the tires. Frontt ires typically
wear more on the shoulders and the rear tires in the center.
On vehicles that have the same size front and
rear wheels, you can rotatet he wheels accord-
ing to the intervals in the tire manufacturer's
warranty book in your vehicle documents. If no
warranty book is available, the tires should be
rotated every 3,000 to 6,000 miles (5,000 to
10,000k m).Earlier may be necessary, depend-
ing on the degree of tire wear. Do not change the
direction of wheel rotation.
Clean the contact surfaces of the wheel and the
brake disc thoroughly every time awheel is rota-
ted. Check the tire pressure and, if necessary,
restart the tire pressure loss warning system
(
Ypage 323) or the tire pressure monitor
(Ypage 325).
Direction of rotation
Tires with aspecified direction of rotation have
additional benefits ,e.g. if there is arisk of hydro-
planing. These advantages can only be gained if
the tires are installed corresponding to the
direction of rotation.
An arrow on the sidewall of the tire indicates its
correctd irection of rotation.
Storing wheels
Storewheels that are not being used in acool,
dry and preferably dark place. Protectt he tires
from oil, grease, gasoline and diesel.
Mounting awheel
Preparing the vehicle
XStop the vehicle on solid, non-slippery and
level ground.
XApply the electric parking brake manually.
XBring the front wheels into the straight-ahead position.
XShift the transmission to position P.
XMake sure that the vehicle level is set to "Nor-
mal" on vehicles with AIRMATIC(Ypage 172).
XSwitch off the engine.
XVehicles without KEYLESS-GO: remove the
SmartKey from the ignition lock.
XVehicles with KEYLESS-GO start-function
or KEYLESS-GO: open the driver's door.
The on-board electronics now have status 0.
This is the same as the SmartKey having been
removed.
XVehicles with KEYLESS-GO start-function
or KEYLESS-GO: remove the Start/Stop but-
ton from the ignition lock (
Ypage 131).
XMake sure that the engine cannot be started
via your smartphon e(Ypage 134).
XIf included in the vehicle equipment, remove
the tire-change tool kit from the vehicle.
XSafeguard the vehicle against rolling away.
Securing the vehicle to prevent it from
rolling away
If your vehicle is equipped with awheel chock,i t
can be found in the vehicle tool kit (Ypage 300).
The folding wheel chock is an additional safety
measure to prevent the vehicle from rolling
away,f or example when changing awheel.
336Changing awheel
Wheels and tires

with thebodyworka nd axle components. This
could result in damage to th etires or th evehi-
cle.
Mercedes-Ben zacceptsnol iabilityfor dam-
age resulting fromt heuse of tires, wheels or
accessories other than those tested and
approved.
Information on tires, wheels and approved
combinations can be obtained froma ny quali-
fied specialist workshop.
!Retreaded tires are neither tested nor rec-
ommended by Mercedes-Benz, since previ-
ous damage cannot always be detected on
retreaded tires. As aresult ,Mercedes-Benz
cannot guarantee vehicle safetyifr etreaded
tires are mounted .Donot mountu sed tires if
you have no information about their previous
usage.
The recommended pressures for various oper-
atin gconditions can be found:
Ron th eTire and LoadingI nformation placard
on th eB-pillar on th edriver's side
Rin th etirep ressure table in th efuel filler flap
Observe th enotes on recommended tir epres-
sures under various operatin gconditions
(
Ypage 319).
Check tir epressures regularly, and only when
th et ires are cold .Comply with th emaintenance
recommendation softhetirem anufacturer in
th ev ehicle documentw allet.
Notes on th evehicle equipment –always equip
th ev ehicle with:
Rwith tires of th esame sizeonag iven axle (left
and right)
Rth es ame type of tires at agiven tim e(summer
tires, winter tires, MOExtended tires)
Exception: it is permissible to install adiffer-
ent type or makeint heeventofaf lat tire.
Observe t
h e"MOExtended tires (tires with
run-flat characteristics" sectio n(Ypage 301).
Vehicles equipped with MOExtended tires are
not equipped with aTIREFIT kit at th efactory. It
is therefore recommended that you additionally
equip your vehicle with aTIREFIT kit if you mount
tires that do not feature run-flat properties, e.g.
winter tires. ATIREFI Tkit may be obtained from
aq ualified specialist workshop.
Wheel-tire combination341
Wheels and tires
Z