2018 MERCEDES-BENZ CLA COUPE Owner's Manual

tire load rating and speedrating required for
your vehicle.
:Tire width
;Nomina laspec tratio in %
=Tire code
?Rimd iame ter
ALoadb earing 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.
Aspec tratio: aspect ratio ;is the size ratio
between the tire height and tire width and is
shown in percent. The aspect ratio is calculated
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 ltire s; "
B" represents diagona
lradial tires.
Optionally ,tire sw itham aximum spee dofover
149 mph (240 km/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 298).
Example:
Load-bearin gindex 91 indicates amaximum
load of 1,356 lb (61 5kg)thatt he tire scan bear.
For furtheri nformation on the maximum tire
load in kilograms and lbs, see(
Ypage 304).
For furtheri nformation on the load bearing
index, see" Loadindex" (
Ypage 304).
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.
Summert ires
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 dtires303
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.E xample:
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 aboutt he 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 312).
Further information aboutr eading tire data can
be obtained from any qualifieds pecialist work-
shop.
Load index
In addition to the load-bearing index, load
index :may be imprinted after the letters that
identify speed rating on the sidewall of the tire.
Speed rating (
Ypage 302).
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.
304Allabout 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 298).
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 312).
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 tires305
Wheels and tires
Z

Uniform TireQualityG rading Standards
Aunifor mstandard to grade the quality of tires
with regards to tread quality, tire traction and
temperature characteristics. The quality grad-
ing assessmentism ade by the manufacturer
following specification sfrom the U.S .govern-
ment .The ratings are molded int othe sidewall of
the tire.
Recommended tir epressures
The recommended tire pressure applies to the
tires mounted at the factory.
The Tire and Loading Information placard con-
tains the recommended tire pressures for cold
tires on afully loaded vehicle and for the maxi-
mum permissible vehicle speed.
The tire pressure table contains the recommen-
ded pressures for cold tires for various operat-
ing conditions, i.e. differingl oad and speed con-
ditions.
Increased vehicle weight due to optional
equipment
The combined weight of all standard and
optional equipment available for the vehicle,
regardless of whether it is actually installed on
the vehicle or not.
Rim
This is the part of the wheel on which the tire is
mounted.
GAWR (Gross Axle Weight Rating)
The GAWR is the maximum gross axle weight
rating. The actual load on an axle must never
exceed the gross axle weight rating. The gross
axle weight ratin gcan be found on the vehicle
identification plate on the B-pillar on the driver's
side.
Speed rating
The speed ratin gispart of the tire identification.
It specifies the speed range for which the tire is
approved.
GVW (Gross Vehicle Weight)
The gross vehicle weight includes the weight of
the vehicle includin gfuel, tools, the spare wheel,
accessories installed, occupants, luggage and
the drawbar noseweight ,ifapplicable. The gross
vehicle weight must not exceed the gross vehi-
cle weight ratin gGVWR as specified on the vehi-
cle identification plate on the B-pillar on the
driver'ss ide.
GVWR(Gross Vehicle Weight Rating)
The GVWR is the maximum permissible gross
weight of afully loaded vehicle (the weight of the
vehicle includin gall accessories, occupants,
fuel, luggage and the drawbar n
oseweight
,if
applicable). The gross vehicle weight ratin gis
specified on the vehicle identification plate on
the B-pillar on the driver'ss ide.
Maximum loaded vehicle weight
The maximum weight is the sum of:
Rthe curb weight of the vehicle
Rthe weight of the accessories
Rthe load limit
Rthe weight of the factory installed optional
equipment
Kilopascal (kPa)
Metric unit for tire pressure. 6.9 kPa corre-
sponds to1psi. Another unit for tire pressure is
bar. 100 kilopascals (kPa) are the equivalent of
1b ar.
Load index
In addition to the load-bearin gindex ,the load
index may also be imprinted on the sidewall of
the tire. This specifies the load-bearin gcapacity
more precisely.
Curb weight
The weight of avehicle with standard equipment
includin gthe maximum capacityoff uel, oil and
coolant .Italso includes the air-conditionin gsys-
tem and optional equipment if these are instal-
led in the vehicle, but does not include passen-
gers or luggage.
Maximum load rating
The maximum tire load is the maximum permis-
sible weight in kilogram sorlbs for which atire is
approved.
Maximum permissible tir epressure
Maximum permissible tire pressure for one tire.
Maximum load on one tire
Maximum load on one tire. This is calculated by
dividing the maximum axle load of one axle by
two.
306All about wheels and tires
Wheels and tires

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 2.3 kg (5 lbs). 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 271) 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 271).
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 awheel307
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.
Observe the instructions and safety notes in the
"Changing awheel" section (
Ypage 307).
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 rotat ethe 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).D ependin gontire wear, this may
be required earlier. 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
(Canada only) or the tire pressure monitor (USA
only).
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 j.
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 vehicle electronics are now in position
u.T his is the same as “key removed”.
XVehicles with KEYLESS-GO start-function
or KEYLESS-GO: remove the Start/Stop but-
ton from the ignition lock (
Ypage 122).
XMake sure that the engine cannot be started
via your smartphon e(Ypage 83).
XIf included in the vehicle equipment, remove
the tire-change tool kit from the vehicle.
XSafeguard the vehicle against rolling away
(Ypage 141).
iApart from certain country-specific varia-
tions, the vehicles are not equipped with a
tire-change tool kit. Some tools for changing a
wheel are specific to the vehicle. For more
information on which tools are required to
perform awheel change on your vehicle, con-
sult aqualified specialist workshop.
Necessary tire-changing tools can include, for
example:
RJack
RWheel chock
RLug wrench
308Changing awheel
Wheels and tires

Securing the vehicle to prevent it from
rolling away
If your vehicle is equippedwithaw heel chock,i t
can be found in the tire-change tool kit
(
Ypage 270).
The folding wheel chock is an additional safety
measure to prevent the vehicle from rolling
away,f or example when changing awheel.
XFold both plates up :.
XFold out lower plate ;.
XGuide the lugs on the lower plate fully into the
openings in base plate =.
XPlace chocksorother suitable items under
the front and rear of the wheel that is diago-
nally opposite the wheel you wish to change.
Raising the vehicle
GWARNING
If you do not position the jack correctly at the
appropriate jackingp oint of the vehicle, the
jack could tip over with the vehicle raised.
There is arisk of injury.
Only position the jack at the appropriate jack-
ing point of the vehicle. The base of the jack
must be positioned vertically, directly under
the jackingp oint of the vehicle.
!Only position the jack at the appropriate
jackingp oint of the vehicle. Otherwise, you
could damage the vehicle.
Observe the following when raising the vehi-
cle:
RTo raise the vehicle, only use the vehicle-spe-
cific jack that has been tested and approved
by Mercedes-Benz. If used incorrectly, the
jack could tip over with the vehicle raised.
RThe jack is designed only to raise and hold the
vehicle for ashort time while awheel is being
changed. It must not be used for performing
maintenance work under the vehicle.
RAvoid changing the wheel on uphill and down-
hill slopes.
RBefore raising the vehicle, secure it from roll-
ing away by applying the parking brake and
insertingw heel chocks. Do not disengage the
parking brake while the vehicle is raised.
RThe jack must be placed on afirm, flat and
non-slip surface. On aloose surface, alarge,
flat, load-bearing underlay must be used. On a
slippery surface, anon-slip underlay must be
used, e.g. rubber mats.
RDo not use wooden blocks or similar objects
as ajack underlay. Otherwise, the jack will not
be able to achieve its load-bearing capacity
due to the restricted height.
RMake sure that the distance between the
underside of the tires and the ground does not
exceed 1.2 in (3 cm).
RNever place your hands and feet under the
raised vehicle.
RDo not lie under the vehicle.
RDo not start the engine when the vehicle is
raised.
RDo not open or close adoor or the trunk lid
when the vehicle is raised.
RMake sure that no persons are present in the
vehicle when the vehicle is raised.
Changing awheel309
Wheels and tires
Z

XUsing lug wrench:,loosen the bolts on the
wheel you wish to change by abouto ne full
turn. Do not unscrew the bolts completely.
Jacking points
The jacking points are located just behind the
front wheel housings and just in front of the rear
wheel housings (arrows).
Mercedes-AMG vehicles and vehicles with
AMG Line: to protect the vehicle body, the vehi-
cle has covers installed next to the jacking
points on the outer sills.
Covers, front (example: vehicles with AMG Line)
XMercedes-AMG vehicles and vehicles
with AMG Line: fold cover;upwards.
XTake ratchet wrench Aout of the vehicle tool
kit and place it on the hexagon nut of jack ?
so that the letters AUFare visible.
XPosition jack ?at jacking point =.
XMake sure the foot of the jack is directly
beneath the jacking point.
XTurn ratchet wrench Auntil jack ?sits
completely on jacking point =and the base
of the jack lies evenly on the ground.
XTurn ratchet wrench Auntil the tire is raised
am aximum of 1.2 in (3 cm )from the ground.
Removing awheel
!Do not place wheel bolts in sand or on adirty
surface. The bolt and wheel hub threads could
otherwise be damagedw hen you screw them
in.
XUnscrew the wheel bolts.
XRemove the wheel.
Mounting anew wheel
GWARNING
Oiled or greased wheel bolts or damaged
wheel bolts/hub threads can cause the wheel
310Changing awheel
Wheels and tires