spare wheel MERCEDES-BENZ M-Class 2012 W166 Owner's Guide

mounted
isnot thesame asthe spare
whee l/emerg encyspare wheel'scurrent
tire pressu re.
Tire pressure monitorwarning
message s If
the tire pressu remonitor detectsa
signifi cantpressu reloss onone ormore tires,
a warni ngmessa geisshow nint he
multifunction display.Aw arning tone also
soun dsand thetir epres sure warninglamp
light sup intheins trumen tcluster .
Eac htir ethat isaffec tedbyasign ificant loss
of press ureishighligh tedwith acolor .
If the Corr
ect Tire Pressure mess
age
appears inthe mult ifunc tiondisplay:
X Check thetirepress ureonallfour wheels
and correctit ifnec essary. i
If
the wheel positionsonthe vehic leare
int erc hang ed,the tirepress uresmaybe
displayed forthe wron gposit ionsfora
shor ttime. Thisisrec tified afterafew
min utes ofdrivin g,and thetirepress ures
are displayed forthe correctpositions.
Restar tingthetire pressur emonitor G
WARNIN
G It
is the driver's responsibility toset the tire
pressure tothe recommen dedcold tire
pressure. Underinflatedtiresaffect theability
to steer orbrake thevehicle. Youmight lose
cont rolover thevehicle.
When yourestart thetire pressure monitor,
all existin gwarning messages aredeleted and
the warning lampsgoout. Themonit oruses
the current lyset tire pressures asthe
referen cevalues formonit oring. Inmost
cases, thetire pressure monitoringsystem
recogn izesthenew referen cevalues
automatically. However,
youcan also define referen ce
values manually asdescribed here:
X Set thetire pressure (Ypage 353)tothe
value recomm endedforthe correspon ding
driving situation onthe Tire andLoading
Infor mation placard onthe driver's side
B-pillar.
Additional tirepressure valuesfordriving
at high speeds orwith heavy loadscanbe
found inthe tire pressure tableonthe
inside ofthe fuel filler flap.
X Make surethatthetire pressure iscorrec t
on allfour wheels.
X Make surethattheSmart Keyisin position
2 in the ignition lock.
X Press the= or; button onthe
steerin gwheel toselect the Serv. menu.
X Press the9 or: button toselect Tire
Pressure .
X Press thea button .
The multifunct iondisplay showsthe
current tirepressure ofthe individual tires
or the Tire
pressure willbe displayed
afterdriving afew minutes message.
X Press the: button .
The Use
Current Pressures asNew Reference
Values message
appearsin
the multifunct iondisplay .
If you wish toconfirm theresta rt:
X Press thea button .
The Tire
Press. Monitor Restarted message
appearsinthe multifunct ion
display .
Aft erdriving forafew minutes, thesystem
check swhether thecurrent tirepressures
are within thespecified range.Thenew tire
pressures arethen accepted asreferen ce
values andmonit ored.
If you wish tocancel theresta rt:
X Press the% button .
The tirepressure valuesstored atthe last
restart willcont inue tobe monit ored. Tir
epr essure
361Wheels and tires Z

Tire
size des ignati on,load -bea ring
cap acit yand speed ratin g :
Tire width
; Nom inalaspec tratio in%
= Tire code
? Rim diame ter
A Load bearingindex
B Spe edrating i
Tire
datais veh icle-spec ificand may
devi atefrom thedat ain theex ample .
Gener al:depen dingon theman ufacturer's
st and ards ,th esiz eimpr inted inthetir ewall
may notco ntain any letters or may contain
on elet tert hat precedes thesize description.
If there isno letter preceding thesize
description (asshown above): theseare
passenger vehicletiresaccording to
European manufacturing standards.
If "P" precedes thesize description: theseare
passenger vehicletiresaccording toU.S.
manufacturing standards.
If "LT" precedes thesize description: these
are light truck tiresaccording toU.S.
manufacturing standards.
If "T" precedes thesize description: theseare
compact emergency sparewheels athigh tire
pressure, tobe used onlytemporarily inan
emergency.
Tire width: tirewidth :shows thenominal
tire width inmillimeters.
Nominal aspectratio: aspect ratio;isthe
size ratio between thetire height andthetire
width andisshown inpercent .The aspect ratio
iscalculated bydividing thetire width by
the tire height.
Tire code: tirecode =specifies thetire type.
"R" represents radialtires."D"represents
diagonal tires,"B"represents diagonalradial
tires.
Optionally, tireswithamaximum speedof
over 149mph(240 km/h)mayhave "ZR"in
the size description dependingonthe
manufacturer (e.g.245/ 40ZR18).
Rim diamet er:rim diameter ?isthe
diameter ofthe bead seat,notthediameter
of the rim flange. Therimdiameter is
specified ininches (in).
Load bearing index:loadbearing indexA
is anumerical codewhich specifies the
maximum load-bearing capacityofatire. G
WARNING The
tireload rating mustalwaysbe atleast
half ofthe GAWR ofyour vehicle. Otherwise,
sudden tirefailure maybethe result which
could cause anaccident and/orserious injury
to you orothers.
Always replace rimsandtires withrims and
tires having thesame specifications
(designation, manufacturer andtype) as
shown onthe original part. G
WARNING Do
not overload thetires byexceeding the
specified loadlimit asindicated onthe Tire
and Loading Informationplacard onthe
driver's doorB-pillar. Overloading thetires
can overheat them,possibly causinga
blowou t.Overloading thetires canalso result
in handling orsteering problems, orbrake
failure.
Example:
The load bearing index91isequiva lenttoa
maximum loadof1356 lbs(615 kg)that the
tire can carry. Forfurther information onthe
maximum tireload inkilograms andpounds,
see (Ypage 365). 368
Tire
labeli ngWheels and tires

Incr
ease dvehicle weight dueto
opt ional equipm ent
This isthecom binedweight ofall standar d
and optionalequipm entavailable forthe
veh icle,regar dless ofwhet heritis act ually
ins talle don theveh icle ornot. Rim
This isthepart ofthew heel onwhich thetire
is mounted. GAWR
(Gross AxleWeight Rating)
The GAWR isthe maximum permissible axle
weight. Theactual loadonanaxle must never
exceed thegross axleweight rating.The
gross axleweight ratingcanbefound onthe
vehicle identification plateonthe B-pillar on
the driver's side. Speed
rating
The speed ratingispart ofthe tire
identification. Itspecifies thespeed rangefor
which thetire isapproved. GTW
(Gross Trailer Weight)
The GTW isthe weight ofatrailer including
the weight ofthe load, luggage,accessories
etc. onthe trailer. GVW
(Gross Vehicle Weight)
The gross vehicle weightcomprises the
weight ofthe vehicle including fuel,tools, the
spare wheel, accessories installed,
occupants, luggageand thedrawba r
noseweight, ifappli cable. Thegross vehicle
weight mustnotexceed thegross vehicle
weight ratingGVWR asspecified onthe
vehicle identification plateonthe Bpillar on
the drive r'sside. GV
WR (Gross Vehicle Weight Rating)
The GVWR isthe maxim umperm issible gross
weight ofafully loaded vehicle(th eweight of
the vehic leinc luding allacc essor ies,
occ upant s,fuel, luggage andthedrawbar
nos eweight ,if applicable). Thegros svehic le
weight rating isspec ified onthe vehic le
ident ification plateonthe B-pillar onthe
drive r'sside. Max
imumload edvehicle weight
The maximum weight isthesum ofthecur b
weight oftheveh icle,th eweight ofthe
acc esso ries,th eto tal load limit andthe
weight oftheopt ionalequipm entinstalle dat
th efac tory. Kilopa
scal(kPa)
Met ricunit fortirepres sure. 6.9kP ais the
equivale ntof1psi .An other unit fortire
pres sure isbar. Thereare 100k ilopasc als
(kPa) to1b ar. Load
index
In addit iontotheload beari ngind ex,th eload
ind exmay alsobeimpr inted on thesidew all
of thetir e. This spec ifiesthe load bearing
capacity moreprecisely. Curb
weight
The weight ofavehicle withstandard
equipment includingthemaximum capacity
of fuel, oiland coolant. Italso includes theair-
condition ingsystem andoptional equipment
if these areinstalled inthe vehicle, butdoes
not include passengers orlugga ge. 372
Defin
itionofterm sfor tires andloadingWheels and tires

Trac
tion
Tra ctio nis the resultof frictio nbe twe enthe
tire sand theroadsu rfa ce. TWR
(Tongue We ight Ratin g)
The TWRsp eci fiesthe maxim um permi ssible
we ight tha tthe ball coupling ofthe trailer tow
hitch cansupport. Tread
wearindicators
Narrow bars(tread wearbars) thatare
distributed overthetire tread. Ifthe tire tread
is level withthebars, thewear limitof1
/ 16 in
(1.6 mm) hasbeen reached. Occupant
distribution
The distribution ofoccupants inavehicle at
their designated seatingpositions. Total
loadlimit
Rated cargoandlugga geload plus
68 kilograms (150lbs)times thevehicle's
designated seatingcapacity. Changing
awhee l Fl
at tire
The "Brea kdown assistance" section
(Y pag e329) contains informationandnotes
on how todea lwith afla ttire. Italso provides
inst ruct ions onchan gingawheel ormoun ting
the spare wheel/ emergencyspare wheel. Inter
chang ingthewheels G
WARN
ING Rotat
efro ntand rear wheels onlyifthe tires
are ofthe same dimen sion. If
your vehic leisequipped withmixed-s ize
tir es (diff eren ttire dimen sionsfro ntvs. rear),
tir erot ation isnot possible . G
WARN
ING Have
thetightening torque chec kedafter
chan gingawheel. Thewheels couldcome
loose ifthe yare not tightenedtoator que of
110 lb-ft(150 Nm).
Only usegenuin eMerc edes- Benzwheel bolts
specified foryour vehicle's rims.
The wear pattern son the front andrear tires
differ, depending onthe operating conditions.
Rotate thewheels beforeaclear wearpattern
has formed onthe tires. Front tirestypically
wear more onthe shoulders andtherear tires
in the cent er.
If your vehicle's tireconfiguration allows,you
can rotate thewheels according tothe
intervals inthe tire manufacturer's warranty
book inyour vehicle documents. Ifthis isnot
availa ble,thetires should thenbereplaced
every 3000to6000 miles
(5000 to10,000 km),orearl ierifthe tire wea r
requ iresthis. Donot change thedirection of
whee lrotation.
Cle anthe contact surfacesofthe whee land
the brake discthoroug hlyevery timeawhee l
is interchanged .Check thetire pressures.
Inform ationonchanging awheel and
mounting thespare wheel (Ypage 333).
! Onvehicles equippedwith atire pressure
monitor, electronic componentsare
located inthe wheel.
Tire-mountin gtools should notbeused
near thevalve. Thiscould damage the
electronic components.
Always havethetires changed ataqual ified
specialist workshop, e.g.anauthorized
Mercedes-Ben zCent er. 374
Changing
awhee lWheels and tires

Dir
ect ion ofrotation
Tir es wit haspe cifie ddir ection ofrotation
hav eaddit ionalben efits, e.g. ifth ere isaris k
of hydr oplaning .Y ou will only gain these
benefits ifthe correc tdirection ofrotat ionis
maintained.
An arrow onthe sidewal lof the tire indicates
its correc tdirection ofrotat ion.
You may mount aspare wheel/emergenc y
spare wheel against thedirection ofrotat ion.
Observe thetime restriction onuse aswell as
the speed limitspecified onthe spare wheel/
emergenc yspare wheel. Storing
wheels
Stor ewheels thatarenot being usedinacool,
dry and preferably darkplace. Protectthe
tires from oil,grease, gasoline anddiesel. Cleanin
gthe wheel s G
WARNING Do
not use power washers withcircular-jet
nozz les(dirt grinders) toclean yourvehicle, in
particular thetires. Youcould otherwise
damage thetires andcause anaccident. Wheel
andtirecombinations Please
bearthefollow inginmind
! For safety reasons, Mercedes-Ben z
recommen dsthat youonly useTires and
wheels whichhavebeen approved by
Mercedes-Ben zspecific allyforyour
vehicle. These
tireshave been specially adaptedfor
use with thecontrolsystems ,such asABS
or ESP®
,and aremark edasfollows:
R MO =Mercedes- BenzOriginal
R MOE =Mercedes- BenzOrigi nal Extended
(tires featuringrun-flat characteristics)
R MO1 =Mercedes- BenzOriginal (only
certain AMGtires)
Mercede s-BenzOriginalExtended tires
may onlybeuse don whee lsthat have been
speci ficallyapp roved byMercede s-Benz.
Only usetires, wheelsor accesso ries
tested andapproved byMercede s-Benz.
Certa inchara cteristics, e.g.handl ing,
vehicl enoise emissionsorfuel
consumptio n,may otherwi sebe adve rsely
affected. Inadd ition, when drivingwith a
loa d,tire dime nsion variations couldcaus e
the tires tocome intocontact withthe
body work andaxle components. Thiscould
resu ltin dama getothe tires orthe vehicl e.
Mercede s-Benzaccepts noliabil ity for
dama geresu lting from theuse oftires,
whee lsor accesso riesother thanthose
tested andapproved.
Further informati onabo uttires, wheelsand
app roved combina tionscanbeobtai ned
from anyauthorized Mercede s-Benz
Center. i
The
Tire andLoad Information placard
with therecommende dtire pressu resis
attached tothe B-pill aron the drive r'sside .
Further informati onabo utdrivi ngathigh
spee dsordrivi ngwith vehicl eloa dsthat are
lig hter than themaximu mvehicle loadcan
be found inthe tire pressure tableonthe
inside ofthe fuel filler flap.Check tire
pressures regularly,andonly when thetires
are cold. Comply withthemaint enanc e
recom mendat ionsofthe tire manufact urer
in the vehicle documen twallet .
For further inform ationon ther ecomm ended
tire inflation pressure andontire pressures
for specific drivingconditions (Ypage 353). Wheel
andtirecombinations
375Wheels and tires Z

Winter
tires32 All
oy whe els V1 V2
BA 255/50
R19107HXL
M+Si MOExtended 31 8.0
Jx 19 H2
Whee loffset: 2.21in(56 mm) # #
BA 255/50
R19107HXL
M+SiMOExtended 30,
31 8.5
Jx 19 H2
Whee loffset: 2.32in(59 mm) # #
"Mini
spare" emerge ncyspare wheel30 Tires Wheel
s V1 V2
T
155/90 R18113M
Tire pressu re:420 kPa(4.2 bar/61 psi) 4
B x18 H2
Whee loffset: 1.58in(40 mm) # #
i
The
speci fiedtirepressu reisprinted inyel low onthe emerge ncysparewhe el.
32 Not available from thefactory.
31 MOExtended tires(tires featuringrun-fla tcharacteristics) onlyincombination withanactivated tirepressure
loss warning systemortire pressure monitor.
30 Use ofsnow chains notpermitted. Observethenotes inthe "Snow chains" section. 378
Wheel
andtirecombinationsWheels and tires