2019 MERCEDES-BENZ SLC spare wheel

Check wheels and tires for damage at leastonce a month. Check wheels and tires afterdriving off-road or on rough roads. Damagedwheels can cause a loss of tire pressure. Payparticular attention to damage such as:
Rcuts in the tires
Rpunctures in the tires
Rtears in the tires
Rbulges on tires
Rdeformation or severe corrosion on wheels
Regularly check the tire tread depth and thecondition of the tread across the whole widthof all tires (Ypage 268). If necessary, turn thefront wheels to full lock in order to inspect theinner side of the tire surface.
All wheels must have a valve cap to protectthe valve against dirt and moisture. Do notmount anything onto the valve other than thestandard valve cap or other valve capsapproved by Mercedes-Benz for your vehicle.Do not use any other valve caps or systems,e.g. tire pressure monitoring systems.
Regularly check the pressure of all the tiresparticularly prior to long trips. Adjust the tirepressure as necessary (Ypage 270).
Observe the notes on the emergency sparewheel (Ypage 293).
The service life of tires depends, among otherthings, on the following factors:
RDriving style
RTire pressure
RDistance covered
Notes on tire tread
GWARNING
If there is insufficient tire tread, the tire trac-
tion decreases. The tire tread is no longer
able to dissipate water. This increases the
risk of hydroplaning when the road surface
is wet, particularly when the vehicle's speed
is not adapted to the road conditions. There
is a risk of an accident.
When the tire pressure is too high or too
low, tires may wear differently at different
points on the tire tread. Therefore, regularly
check the tire tread depth and the condition
of the tread across the whole width of all
tires.
Minimum tire tread depth on:
RSummer tires:

Snow chains
GWARNING
If snow chains are installed to the front
wheels, they may drag against the vehicle
body or chassis components. This could
cause damage to the vehicle or the tires.
There is a risk of an accident.
To avoid hazardous situations:
Rnever install snow chains to the front
wheels
Ralways install snow chains in pairs to the
rear wheels.
For safety reasons, Mercedes-Benz recom-mends that you only use snow chains thathave been specially approved for your vehicleby Mercedes-Benz, or are of a correspondingstandard of quality. For more information,please contact a qualified specialist workshop.
If you intend to mount snow chains, pleasebear the following points in mind:
RSnow chains may not be mounted on allwheel/tire combinations. Permissiblewheel-tire combinations (Ypage 292).
ROnly use snow chains when driving on roadscompletely covered by snow. Remove thesnow chains as soon as possible when youcome to a road that is not snow-covered.
RLocal regulations may restrict the use ofsnow chains. Observe the appropriate regu-lations if you wish to mount snow chains.
RDo not exceed the maximum permissiblespeed of 30 mph (50 km/h).
You may wish to deactivate ESP®when pullingaway with snow chains installed (Ypage 61).You can thereby allow the wheels to spin in acontrolled manner, achieving an increaseddriving force (cutting action).
Information about driving with an emergencyspare wheel (Ypage 293).
Tire pressure
Tire pressure specifications
Important safety notes
GWARNING
Underinflated or overinflated tires pose the
following risks:
Rthe tires may burst, especially as the load
and vehicle speed increase.
Rthe tires may wear excessively and/or
unevenly, which may greatly impair tire
traction.
Rthe driving characteristics, as well as
steering and braking, may be greatly
impaired.
There is a risk of an accident.
Follow recommended tire inflation pressures
and check the pressure of all the tires
including the spare wheel:
Rmonthly, at least
Rif the load changes
Rbefore beginning a long journey
Runder different operating conditions, e.g.
off-road driving
If necessary, correct the tire pressure.
The data on the Tire and Loading Informationplacard and tire pressure table shown here areexamples. Tire pressure specifications arevehicle-specific and may deviate from the datashown here. The tire pressure specificationsthat are valid for your vehicle can be found onthe Tire and Loading Information placard andtire pressure table on the vehicle.
General notes
The recommended tire pressures for the tiresmounted at the factory can be found on thelabels described here.
Operation with an emergency spare wheel:information on operation with an emergencyspare wheel can be found in the general notesin the "Emergency spare wheel" section(Ypage 294).
Further information on tire pressures can beobtained at a qualified specialist workshop.
270Tire pressure
Wheels and tires

Important notes on tire pressure
GWARNING
If the tire pressure drops repeatedly, the
wheel, valve or tire may be damaged. Tire
pressure that is too low may result in a tire
blow-out. There is a risk of an accident.
RCheck the tire for foreign objects.
RCheck whether the wheel is losing air or
the valve is leaking.
If you are unable to rectify the damage, con-
tact a qualified specialist workshop.
GWARNING
If you fit unsuitable accessories onto tire
valves, the tire valves may be overloaded
and malfunction, which can cause tire pres-
sure loss. Due to their design, retrofitted tire
pressure monitors keep the tire valve open.
This can also result in tire pressure loss.
There is a risk of an accident.
Only screw the standard valve cap or other
valve caps approved by Mercedes-Benz for
your vehicle onto the tire valve.
Use a suitable pressure gauge to check thetire pressure. The outer appearance of a tiredoes not permit any reliable conclusion aboutthe tire pressure. On vehicles equipped withthe electronic tire pressure monitor, the tirepressure can be checked in the on-board com-puter.
The tire temperature and pressure increasewhen the vehicle is in motion. This is depend-ent on the driving speed and the load.
Therefore, you should only correct tire pres-sures when the tires are cold.
The tires are cold:
Rif the vehicle has been parked with the tiresout of direct sunlight for at least three hoursand
Rif the vehicle has not been driven furtherthan 1 mile (1.6 km)
The tire temperature changes depending onthe outside temperature, the vehicle speedand the tire load. If the tire temperaturechanges by 18 ‡ (10 †), the tire pressurechanges by approximately 10 kPa (0.1 bar/1.5 psi). Take this into account when checking
the pressure of warm tires. Only correct thetire pressure if it is too low for the currentoperating conditions. If you check the tirepressure when the tires are warm, the result-ing value will be higher than if the tires werecold. This is normal. Do not reduce the tirepressure to the value specified for cold tires.The tire pressure would otherwise be too low.
Observe the recommended tire pressures forcold tires:
Ron the Tire and Loading Information placardon the B-pillar on the driver's side
Rin the tire pressure table on the inside of thefuel filler flap
Rprinted in yellow on the rim of the emer-gency/collapsible spare wheel (dependingon vehicle equipment)
Underinflated or overinflated tires
Underinflated tires
GWARNING
Tires with pressure that is too low can over-
heat and burst as a consequence. In addi-
tion, they also suffer from excessive and/or
irregular wear, which can severely impair the
braking properties and the driving character-
istics. There is a risk of an accident.
Avoid tire pressures that are too low in all
the tires, including the spare wheel.
Underinflated tires may:
Roverheat, leading to tire defects
Radversely affect handling
Rwear excessively and/or unevenly
Rhave an adverse effect on fuel consumption
Overinflated tires
GWARNING
Tires with excessively high pressure can
burst because they are damaged more eas-
ily by road debris, potholes etc. In addition,
they also suffer from irregular wear, which
can severely impair the braking properties
and the driving characteristics. There is a
risk of an accident.
272Tire pressure
Wheels and ti res

Avoid tire pressures that are too high in all
the tires, including the spare wheel.
Overinflated tires may:
Rincrease the braking distance
Radversely affect handling
Rwear excessively and/or unevenly
Rhave an adverse effect on ride comfort
Rbe more susceptible to damage
Maximum tire pressures
CExample: maximum permissible tire pres-sure
Never exceed the maximum permissible tireinflation pressure. Always observe the recom-mended tire pressure for your vehicle whenadjusting the tire pressure (Ypage 270).
iThe actual values for tires are vehicle-spe-cific and may deviate from the values in theillustration.
Checking the tire pressures
Important safety notes
The tire pressure monitor does not warn youof:
Rincorrectly set tire pressure
Rsudden loss of tire pressure, e.g. from a for-eign object that has penetrated the tire
Observe the notes on tire pressure(Ypage 270).
Information on air pressure for the tires onyour vehicle can be found:
Ron the vehicle's Tire and Loading Informa-tion placard on the B-pillar
Ron the tire pressure table in the fuel fillerflap
Rin the "Tire pressure" section
Checking tire pressures manually
To determine and set the correct tire pressure,proceed as follows:
XRemove the valve cap of the tire that is tobe checked.
XPress the tire pressure gauge securely ontothe valve.
XRead the tire pressure and compare it to therecommended value on the Tire and LoadingInformation placard or the tire pressuretable (Ypage 270).
XIf the tire pressure is too low, increase thetire pressure to the recommended value.
XIf the tire pressure is too high, release air.To do so, press down the metal pin in thevalve, using the tip of a pen for example.Then check the tire pressure again using thetire pressure checker.
XScrew the valve cap onto the valve.
XRepeat these steps for the other tires.
Tire pressure loss warning system
(Canada only)
General notes
While the vehicle is in motion, the tire pres-sure loss warning system monitors the set tirepressure using the rotational speed of thewheels. This enables the system to detect sig-nificant pressure loss in a tire. If the speed ofrotation of a wheel changes as a result of aloss of pressure, a corresponding warningmessage will appear in the multifunction dis-play.
You can recognize the tire pressure loss warn-ing by theRun Flat Indicator ActiveRun Flat Indicator ActivePress 'OK' to RestartPress 'OK' to Restartmessage whichappears in theServ.Serv.menu of the multifunc-tion display. Information on the message dis-play can be found in the "Restarting the tire
Tire pressure273
Wheels and tires
Z

is shown in theServ.Serv.menu of the multifunc-tion display.
Example: current tire pressure display
For information on the message display, referto the "Checking the tire pressure electroni-cally" section (Ypage 276).
Important safety notes
GWARNING
Each tire, including the spare (if provided),
should be checked at least once a month
when cold and inflated to the pressure rec-
ommended by the vehicle manufacturer on
the Tire and Loading Information placard on
the driver's door B-pillar or the tire pressure
label on the inside of the fuel filler flap. If
your vehicle has tires of a different size than
the size indicated on the Tire and Loading
Information placard or the tire pressure
label, you should determine the proper tire
pressure for those tires.
As an added safety feature, your vehicle has
been equipped with a tire pressure monitor-
ing system (TPMS) that illuminates a low tire
pressure telltale when one or more of your
tires are significantly underinflated. Accord-
ingly, when the low tire pressure telltale illu-
minates, you should stop and check your
tires as soon as possible, and inflate them to
the proper pressure. Driving on a signifi-
cantly underinflated tire causes the tire to
overheat and can lead to tire failure. Under-
inflation also reduces fuel efficiency and tire
tread life, and may affect the vehicle's han-
dling and stopping ability.
Please note that the TPMS is not a substi-
tute for proper tire maintenance, and it is
the driver's responsibility to maintain cor-
rect 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 if 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 warning lamp will
flash for approximately a minute and then
remain continuously illuminated. This
sequence will be repeated every time the
vehicle is started as long as the malfunction
exists.
When the malfunction indicator is illumina-
ted, the system may not be able to detect or
signal low tire pressure as intended. TPMS
malfunctions may occur for a variety of rea-
sons, including the installation of incompati-
ble replacement or alternate tires or wheels
on the vehicle that prevent the TPMS from
functioning properly. Always check the
TPMS malfunction telltale after replacing
one or more tires or wheels on your vehicle
to ensure that the replacement or alternate
tires and wheels allow the TPMS to continue
to function properly.
It is the driver's responsibility to set the tirepressure to that recommended for cold tireswhich is suitable for the operating situation(Ypage 270). Note that the correct tire pres-sure for the current operating situation mustfirst be taught-in to the tire pressure monitor.If a substantial loss of pressure occurs, thewarning threshold for the warning message isaligned to the taught-in reference values.Restart the tire pressure monitor after adjust-ing the pressure of the cold tires(Ypage 277). The current pressures aresaved as new reference values. As a result, awarning message will appear if the tire pres-sure drops significantly.
The tire pressure monitor does not warn you ofan incorrectly set tire pressure. Observe thenotes on the recommended tire pressure(Ypage 270).
The tire pressure monitor is not able to warnyou of a sudden loss of pressure, e.g. if thetire is penetrated by a foreign object. In theevent of a sudden loss of pressure, bring the
Tire pressure275
Wheels and tires
Z

vehicle to a halt by braking carefully. Avoidabrupt steering movements.
The tire pressure monitor has a yellow warninglamp in the instrument cluster for indicatingpressure loss or a malfunction. Whether thewarning lamp flashes or lights up indicateswhether a tire pressure is too low or the tirepressure monitor is malfunctioning:
Rif the warning lamp is lit continuously, thetire pressure on one or more tires is signifi-cantly too low. The tire pressure monitor isnot malfunctioning.
Rif the warning lamp flashes for approx-imately a minute and then remains lit con-stantly, the tire pressure monitor is malfunc-tioning.
In addition to the warning lamp, a messageappears in the multifunction display. Observethe information on display messages(Ypage 201).
It may take up to ten minutes for a malfunc-tion of the tire pressure monitor to be indica-ted. A malfunction will be indicated by the tirepressure warning lamp flashing for approx-imately one minute and then remaining lit.When the malfunction has been rectified, thetire pressure warning lamp goes out after afew minutes of driving.
The tire pressure values indicated by the on-board computer may differ from those meas-ured at a gas station with a pressure gage. Thetire pressures shown by the on-board com-puter refer to those measured at sea level. Athigh altitudes, the tire pressure values indica-ted by a pressure gage are higher than thoseshown by the on-board computer. In this case,do not reduce the tire pressures.
The operation of the tire pressure monitor canbe affected by interference from radio trans-mitting equipment (e.g. radio headphones,two-way radios) that may be being operated inor near the vehicle.
Checking the tire pressure electroni-
cally
XMake sure that the SmartKey is in positionH(Ypage 118) in the ignition lock.
XPress theYorebutton on the steer-ing wheel to select theServ.Serv.menu.
XPress thecordbutton to selectTire PressureTire Pressure.
XPressv.The current tire pressure of each tire isshown in the multifunction display.
If the vehicle has been parked for over20 minutes, theTire pressure will beTire pressure will bedisplayed after driving a few minutesdisplayed after driving a few minutesmessage appears.
After a teach-in process, the tire pressuremonitor automatically detects new wheels ornew sensors. As long as a clear allocation ofthe tire pressure value to the individual wheelsis not possible, theTire Pressure MonitorTire Pressure MonitorActiveActivedisplay message is shown instead ofthe tire pressure display. The tire pressuresare already being monitored.
If an emergency spare wheel is mounted, thesystem may continue to show the tire pressureof the wheel that has been removed for a fewminutes. Be aware that the value displayed forthe position where the emergency spare wheelis fitted is not the same as the current tirepressure of the emergency spare wheel.
Tire pressure monitor warning mes-
sages
The tire pressure monitor detects a pressureloss in one or more tires:
RIf the tire pressure monitor detects a pres-sure loss in one or more tires, a warningmessage is shown in the multifunction dis-play. The yellow tire pressure warning lampthen lights up.
RIf thePlease Correct Tire PressurePlease Correct Tire Pressuremessage appears in the multifunction dis-play, the tire pressure in at least one tire istoo low. The tire pressure must be correctedwhen the opportunity arises.
RIf theCheck TiresCheck Tiresmessage appears in themultifunction display, the tire pressure in atleast one tire has dropped significantly. Thetires must be checked.
RIf theWarning Tire MalfunctionWarning Tire Malfunctionmes-sage appears in the multifunction display,the tire pressure in at least one tire hasdropped suddenly. The tires must bechecked.
Observe the instructions and safety notes inthe display messages in the "Tires" section(Ypage 201).
276Tire pressure
Wheels and tires

Rim
This is the part of the wheel on which the tireis mounted.
GAWR (Gross Axle Weight Rating)
The GAWR is the maximum gross axle weightrating. The actual load on an axle must neverexceed the gross axle weight rating. The grossaxle weight rating can be found on the vehicleidentification plate on the B-pillar on the driv-er's side.
Speed rating
The speed rating is part of the tire identifica-tion. It specifies the speed range for which thetire is approved.
GVW (Gross Vehicle Weight)
The gross vehicle weight includes the weightof the vehicle including fuel, tools, the sparewheel, accessories installed, occupants, lug-gage and the drawbar noseweight, if applica-ble. The gross vehicle weight must not exceedthe gross vehicle weight rating GVWR as speci-fied on the vehicle identification plate on theB-pillar on the driver's side.
GVWR (Gross Vehicle Weight Rating)
The GVWR is the maximum permissible grossweight of a fully loaded vehicle (the weight ofthe vehicle including all accessories, occu-pants, fuel, luggage and the drawbar nose-weight, if applicable). The gross vehicle weightrating is specified on the vehicle identificationplate on the B-pillar on the driver's side.
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 optionalequipment
Kilopascal (kPa)
Metric unit for tire pressure. 6.9 kPa corre-sponds to 1 psi. Another unit for tire pressureis bar. 100 kilopascals (kPa) are the equivalentof 1 bar.
Load index
In addition to the load-bearing index, the loadindex may also be imprinted on the sidewall ofthe tire. This specifies the load-bearing capa-city more precisely.
Curb weight
The weight of a vehicle with standard equip-ment including the maximum capacity of fuel,oil and coolant. It also includes the air-condi-tioning system and optional equipment if theseare installed in the vehicle, but does notinclude passengers or luggage.
Maximum load rating
The maximum load rating is the maximum per-missible weight in kilograms or lbs for which atire is approved.
Maximum permissible tire pressure
Maximum permissible tire pressure for onetire.
Maximum load on one tire
Maximum load on one tire. This is calculatedby dividing the maximum axle load of one axleby two.
PSI (pounds per square inch)
A standard unit of measure for tire pressure.
Aspect ratio
Relationship between tire height and tire widthin percent.
Tire pressure
This is pressure inside the tire applying an out-ward force to each square inch of the tire'ssurface. The tire pressure is specified inpounds per square inch (psi), in kilopascal(kPa) or in bar. The tire pressure should onlybe corrected when the tires are cold.
Cold tire pressure
The tires are cold:
Rif the vehicle has been parked with the tiresout of direct sunlight for at least three hoursand
Rif the vehicle has not been driven furtherthan 1 mile (1.6 km)
All about wheels and tires287
Wheels and tires
Z

!To prevent damage to the paintwork, holdthe wheel securely against the wheel hubwhile screwing in the first wheel bolt.
XClean the wheel and wheel hub contact sur-faces.
XSlide the wheel to be mounted onto thealignment bolt and push it on.
XTighten the wheel bolts until they are finger-tight.
XUnscrew the alignment bolt.
XTighten the last wheel bolt until it is finger-tight.
XVehicles with a collapsible spare wheel:inflate the collapsible spare wheel(Ypage 295).Only then lower the vehicle.
Lowering the vehicle
GWARNING
The wheels could come loose if the wheel
bolts or wheel nuts are not tightened to the
prescribed tightening torque. There is a risk
of an accident.
Ensure that the wheel bolts or wheel nuts
are tightened to the prescribed tightening
torque.
If you are not sure, do not move the vehicle.
Contact a qualified specialist workshop and
have the tightening torque checked immedi-
ately.
!Vehicles with a collapsible sparewheel:before lowering the vehicle, inflatethe collapsible spare wheel with the tireinflation compressor. The wheel rim couldotherwise be damaged.
XTurn the crank of the jack counter-clockwiseuntil the vehicle is once again standingfirmly on the ground.
XPlace the jack to one side.
XTighten the wheel bolts evenly in a cross-wise pattern in the sequence indicated (Cto