flat tire MERCEDES-BENZ GLS 2019 Owner's Manual

Important safety notes
G
WARNING
If you install wheels and tires with incorrect
dimensions, the service brake or wheel sus-
pension components may be damaged. There is a risk of an accident.
Always replace wheels and tires with ones
that comply with the specifications of the
original part.
When replacing wheels, pay attention to the:
R Designation
R Model
When replacing tires, pay attention to the:
R Designation
R Manufacturer
R Model G
WARNING
A flat tire will severely affect the driving char- acteristics as well as the steering and braking
of the vehicle. There is a risk of an accident.
Tires without run-flat characteristics:
R Do not drive on with a flat tire.
R Change the flat tire immediately with an
emergency spare wheel or spare wheel.
Alternatively, consult a qualified specialist
workshop.
Tires with run-flat characteristics:
R Observe the information and warning notes
on MOExtended tires (run-flat tires).
Accessories that are not approved for your vehi-
cle by Mercedes-Benz or are not being used cor- rectly can impair the operating safety.
Before purchasing and using non-approved
accessories, visit a qualified specialist work-
shop and inquire about:
R suitability
R legal stipulations
R factory recommendations
Further information regarding wheels and tires
can be found under "Wheel/tire combinations"
(Y page 377). You can ask for information regarding permitted
wheel/tire combinations at an authorized
Mercedes-Benz Center.
Tire pressure information can be found:
R on the Tire and Loading Information placard
on the B-pillar on the driver's side
R in the tire pressure table in the fuel filler flap
R in the "Tire pressure" section Operation
Information on driving
Check the tire pressure when the vehicle is
heavily laden and adjust prior to a trip.
While driving, pay attention to vibrations, noises and unusual handling characteristics, e.g. pull-
ing to one side. This may indicate that the
wheels or tires are damaged. If you suspect that
a tire is defective, reduce your speed immedi-
ately. Stop the vehicle as soon as possible to
check the wheels and tires for damage. Hidden tire damage could also be causing the unusual
handling characteristics. If you find no signs of
damage, have the tires and wheels checked at a
qualified specialist workshop.
When parking your vehicle, make sure that the
tires do not get deformed by the curb or other
obstacles. If it is necessary to drive over curbs,
speed humps or similar elevations, try to do so
slowly and at an obtuse angle. Otherwise, the
tires, particularly the sidewalls, may be dam-
aged. Regular checking of wheels and tires
G
WARNING
Damaged tires can cause tire inflation pres-
sure loss. As a result, you could lose control of your vehicle. There is a risk of accident.
Check the tires regularly for signs of damage
and replace any damaged tires immediately.
Check wheels and tires for damage at least once a month. Check wheels and tires after driving
off-road or on rough roads. Damaged wheels
can cause a loss of tire pressure.
Pay particular attention to damage such as:
R cuts in the tires
R punctures in the tires 352
OperationWheels and ti
res

R
tears in the tires
R bulges on tires
R deformation or severe corrosion on wheels
Regularly check the tire tread depth and the
condition of the tread across the whole width of
all tires (Y page 353). If necessary, turn the
front wheels to full lock in order to inspect the
inner side of the tire surface.
All wheels must have a valve cap to protect the
valve against dirt and moisture. Do not mount
anything onto the valve other than the standard valve cap or other valve caps approved 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 tires par- ticularly prior to long trips. Adjust the tire pres-
sure as necessary (Y page 355).
Observe the notes on the emergency spare
wheel (Y page 378).
The service life of tires depends, among other
things, on the following factors:
R Driving style
R Tire pressure
R Distance covered Notes on tire tread
G
WARNING
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:
R Summer tires: 00CEin (3 mm)
R M+S tires: 00CFin (4 mm)
For safety reasons, have the tires replaced
before they reach the legally prescribed min-
imum tire tread depth. Marking
0043shows where the bar indicator
(arrow) for tread wear is integrated into the tire
tread.
Treadwear indicators (TWI) are required by law. Six indicators are positioned on the tire tread.
They are visible once a tread depth of approx-
imately 00CDin (1.6 mm) has been reached. If this
is the case, the tire is so worn that it must be
replaced. Selecting, mounting and replacing
tires
R Only mount tires and wheels of the same type
and make.
Exception: it is permissible to mount a differ-
ent type or make in the event of a flat tire.
Observe here the "MOExtended tires (tires
with run-flat characteristics)" section
(Y page 336).
R Only mount tires of the correct size onto the
wheels.
R Break in new tires at moderate speeds for the
first 60 miles (100 km). The new tires only
reach their full performance after this dis-
tance.
R Do not drive with tires which have too little
tread depth. This significantly reduces the
traction on wet roads (hydroplaning).
R Replace the tires after six years at the latest,
regardless of wear.
Observe the notes on the emergency spare
wheel (Y page 378). MOExtended tires (tires with run-flat
properties)
With MOExtended tires (tires with run flat char- acteristics), you can continue to drive your vehi- Operation
353Wheels and tires Z

cle even if there is a total loss of pressure in one
or more tires.
MOExtended tires may only be used in conjunc-
tion with an active tire pressure loss warning
system or with an active tire pressure monitor
and on wheels specifically tested by Mercedes- Benz.
Notes on driving with MOExtended tires with a
flat tire (Y page 336).
i Vehicles equipped with MOExtended tires
are not equipped with a TIREFIT kit at the fac- tory. It is therefore recommended that you
additionally equip your vehicle with a TIREFIT
kit if you mount tires that do not feature run- flat characteristics, e.g. winter tires. A TIREFIT
kit may be obtained from a qualified specialist
workshop. Winter operation
General notes
Have your vehicle winter-proofed at a qualified
specialist workshop at the onset of winter.
Observe the notes in the "Changing a wheel"
section (Y page 372). Driving with summer tires
At temperatures below 45 ‡ (+7 †), the elas-
ticity of summer tires and therefore also the
traction and braking capability are reduced con-
siderably. Change the tires on your vehicle to
M+S tire s. Using su mmer tires at very cold tem-
peratures could cause cracks to form, thereby
damaging the tires permanently. Mercedes-
Benz cannot accept responsibility for this type
of damage. G
WARNING
Damaged tires can cause tire inflation pres-
sure loss. As a result, you could lose control of your vehicle. There is a risk of accident.
Check the tires regularly for signs of damage
and replace any damaged tires immediately. M+S tires
G
WARNING
M+S tires with a tire tread depth of less than
00CF in (4 mm) are not suitable for use in winter
and do not provide sufficient traction. There is
a risk of an accident.
M+S tires with a tread depth of less than 00CFin
(4 mm) must be replaced immediately.
At temperatures below 45 ‡(+7 †), use winter
tires or all-season tires. Both types of tire are
identified by the M+S marking.
Only winter tires bearing the 004Dsnowflake
symbol in addition to the M+S marking provide
the best possible grip in wintry road conditions.
Only these tires will allow driving safety systems
such as ABS and ESP ®
to function optimally in
winter. These tires have been developed specif-
ically for driving in snow.
Use M+S tires of the same make and tread on all wheels to maintain safe handling characteris-
tics.
Always observe the maximum permissible
speed specified for the M+S tires you have
mounted.
Once the winter tires are mounted:
X Check the tire pressures (Y page 358).
X Restart the tire pressure monitor
(Y page 359).
X Vehicles for Canada: restart the tire pres-
sure loss warning system (Y page 359).
Information about driving with an emergency
spare wheel (Y page 378). Snow chains
G
WARNING
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. 354
Winter operationWheels and tires

To avoid hazardous situations:
R never install snow chains to the front
wheels
R always install snow chains in pairs to the
rear wheels.
! Check the snow chains for damage before
mounting them. Damaged or worn snow
chains may snap and damage the following
components:
R wheel
R wheel housing
R wheel suspension
For this reason, you must use only snow
chains that are free of defects. Observe the
manufacturer's mounting instructions.
! You must drive at raised vehicle level (height
1) if snow chains have been installed. The
vehicle may otherwise be damaged.
! Vehicles with ADS (Adaptive Damping
System): do not use the sport mode when
driving with snow chains mounted. The vehi-
cle may otherwise be damaged.
For safety reasons, Mercedes-Benz recom-
mends that you only use snow chains that have been specially approved for your vehicle by
Mercedes-Benz, or are of a corresponding
standard of quality. For more information,
please contact a qualified specialist workshop.
Install the snow chains on all driven wheels for
maximum tractive power and driving stability. If
you own snow chains for two driven wheels only, install the snow chains to the wheels on the rear
axle. The vehicle then remains more stable
under braking.
If you intend to mount snow chains, please bear
the following points in mind:
R Snow chains may not be mounted on all
wheel/tire combinations. Permissible
wheel/tire combinations (Y page 377).
R Only use snow chains when driving on roads
completely covered by snow. Remove the
snow chains as soon as possible when you
come to a road that is not snow-covered.
R Local regulations may restrict the use of snow
chains. Observe the appropriate regulations if
you wish to mount snow chains. R
Do not exceed the maximum permissible
speed of 30 mph (50 km/h).
R When snow chains are installed, never use
Active Parking Assist (Y page 192) or the
Parking Package with rear view camera.
You may wish to deactivate ESP ®
(Y page 71)
when pulling away with snow chains mounted.
You can thereby allow the wheels to spin in a
controlled manner, achieving an increased driv-
ing force (cutting action).
Information about driving with an emergency
spare wheel (Y page 378). Tire pressure
Tire pressure specifications
Important safety notes G
WARNING
Underinflated or overinflated tires pose the
following risks:
R the tires may burst, especially as the load
and vehicle speed increase.
R the tires may wear excessively and/or
unevenly, which may greatly impair tire
traction.
R the driving characteristics, as well as steer-
ing 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 includ-
ing the spare wheel:
R monthly, at least
R if the load changes
R before beginning a long journey
R under different operating conditions, e.g.
off-road driving
If necessary, correct the tire pressure.
Details on tire pressure can be found at the fol-
lowing positions in the vehicle:
R Tire and Loading Information placard on the
B-pillar on the driver's side
R Table for tire pressure on the inside of the fuel
filler flap
The tire pressure monitor does not warn you of: Tire pressure
355Wheels and tires Z

Some tire pressure tables show only the rim
diameters instead of the full tire size, e.g. R18.
The rim diameter is part of the tire size and can
be found on the tire sidewall (Y page 367).
If the tire pressures have been set to the lower
values for lighter loads and/or lower road
speeds, the pressures should be reset to the
higher values:
R if you want to drive with an increased load
and/or
R if you want to drive at higher speeds
The tire pressures for increased loads and/or
higher road speeds, shown in the tire pressure
table, may have a negative effect on driving
comfort.
If the tire pressure is not set correctly, this can
lead to an excessive build up of heat and a sud- den loss of pressure.
For more information, contact a qualified spe-
cialist workshop. Important notes on tire pressure
G
WARNING
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. R Check the tire for foreign objects.
R Check 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. G
WARNING
If you fit unsuitable accessories onto tire
valves, the tire valves may be overloaded and malfunction, which can cause tire pressure
loss. Due to their design, retrofitted tire pres- sure 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 the tire
pressure. The outer appearance of a tire does not permit any reliable conclusion about the tire
pressure. On vehicles equipped with the elec-
tronic tire pressure monitor, the tire pressure
can be checked in the on-board computer.
The tire temperature and pressure increase
when the vehicle is in motion. This is dependent
on the driving speed and the load.
Therefore, you should only correct tire pres-
sures when the tires are cold.
The tires are cold:
R if the vehicle has been parked with the tires
out of direct sunlight for at least three hours
and
R if the vehicle has not been driven further than
1 mile (1.6 km)
The tire temperature changes depending on the
outside temperature, the vehicle speed and the
tire load. If the tire temperature changes by
18 ‡ (10 †), the tire pressure changes by
approximately 10 kPa (0.1 bar/1.5 psi). Take
this into account when checking the pressure of
warm tires. Only correct the tire pressure if it is too low for the current operating conditions. If
you check the tire pressure when the tires are
warm, the resulting value will be higher than if
the tires were cold. This is normal. Do not
reduce the tire pressure to the value specified
for cold tires. The tire pressure would otherwise
be too low.
Observe the recommended tire pressures for
cold tires:
R on the Tire and Loading Information placard
on the B-pillar on the driver's side
R in the tire pressure table in the fuel filler flap
(Y page 156)
R printed in yellow on the rim of the emer-
gency/collapsible spare wheel (depending on
vehicle equipment) Underinflated or overinflated tires
Underinflated tires G
WARNING
Tires with pressure that is too low can over-
heat and burst as a consequence. In addition, they also suffer from excessive and/or irreg-
ular wear, which can severely impair the brak-ing properties and the driving characteristics.There is a risk of an accident. Tire pressure
357Wheels and tires
Z

Avoid tire pressures that are too low in all the
tires, including the spare wheel.
Underinflated tires may:
R overheat, leading to tire defects
R adversely affect handling
R wear excessively and/or unevenly
R have an adverse effect on fuel consumption
Overinflated tires G
WARNING
Tires with excessively high pressure can burst
because they are damaged more easily 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.
Avoid tire pressures that are too high in all the
tires, including the spare wheel.
Overinflated tires may: R increase the braking distance
R adversely affect handling
R wear excessively and/or unevenly
R have an adverse effect on ride comfort
R be more susceptible to damage
Maximum tire pressures 0043
Example: maximum permissible tire pres-
sure
Never exceed the maximum permissible tire
inflation pressure. Always observe the recom-
mended tire pressure for your vehicle when
adjusting the tire pressure (Y page 355).i
The actual values for tires are vehicle-spe-
cific and may deviate from the values in the
illustration. Checking the tire pressures
Important safety notes Observe the notes on tire pressure
(Y
page 355).
Information on air pressure for the tires on your vehicle can be found:
R on the Tire and Loading Information placard
on the B-pillar on the driver's side
R in the tire pressure table in the fuel filler flap
R in the "Tire pressure" section
Checking tire pressures manually To determine and set the correct tire pressure,
proceed as follows:
X Remove the valve cap of the tire that is to be
checked.
X Press the tire pressure gage securely onto the
valve.
X Read the tire pressure and compare it to the
recommended value on the Tire and Loading
Information placard or the tire pressure table
(Y page 355).
X If the tire pressure is too low, increase the tire
pressure to the recommended value.
X If the tire pressure is too high, release air. To
do so, press down the metal pin in the valve,
using the tip of a pen for example. Then check the tire pressure again using the tire pressure
checker.
X Screw the valve cap onto the valve.
X Repeat these steps for the other tires. Tire pressure loss warning system
General notes While the vehicle is in motion, the tire pressure
loss warning system monitors the set tire pres-
sure using the rotational speed of the wheels.
This enables the system to detect significant
pressure loss in a tire. If the speed of rotation of
a wheel changes as a result of a loss of pressure, 358
Tire pressureWheels and tires

a corresponding warning message will appear in
the multifunction display.
You can recognize the tire pressure loss warning
by the Run Flat Indicator Active Press Run Flat Indicator Active Press
'OK' to Restart
'OK' to Restart message which appears in
the Service
Service menu of the multifunction display.
Information on the message display can be
found in the "Restarting the tire pressure loss
warning system" section (Y page 359).
Important safety notes The tire pressure warning system does not warn
you of an incorrectly set tire pressure. Observe
the notes on the recommended tire pressure
(Y page 355).
The tire pressure loss warning does not replace
the need to regularly check the tire pressure. An even loss of pressure on several tires at the
same time cannot be detected by the tire pres-
sure loss warning system.
The tire pressure monitor is not able to warn you of a sudden loss of pressure, e.g. if the tire is
penetrated by a foreign object. In the event of a
sudden loss of pressure, bring the vehicle to a
halt by braking carefully. Avoid abrupt steering
movements.
The function of the tire pressure loss warning
system is limited or delayed if:
R snow chains are mounted on your vehicle's
tires.
R road conditions are wintry.
R you are driving on sand or gravel.
R you adopt a very sporty driving style (corner-
ing at high speeds or driving with high rates of
acceleration).
R you are driving with a heavy load (in the vehi-
cle or on the roof).
Restarting the tire pressure loss warn-
ing system Restart the tire pressure loss warning system if
you have:
R changed the tire pressure
R changed the wheels or tires
R mounted new wheels or tires
X Before restarting, make sure that the tire
pressures are set properly on all four tires for
the respective operating conditions.
The recommended tire pressure can be found on the Tire and Loading Information placard on the B-pillar. Additionally, a tire pressure
table is attached to the fuel filler flap. The tire
pressure loss warning system can only give
reliable warnings if you have set the correct
tire pressure. If an incorrect tire pressure is
set, these incorrect values will be monitored.
X Also observe the notes in the section on tire
pressures (Y page 355).
X Make sure that the SmartKey is in position 0048
in the ignition lock (Y page 140).
X Press the 0059or0065 button on the steering
wheel to select the Service
Service menu.
X Press the 0063or0064 button to select
Tire Pressure Tire Pressure.
X Press the 0076button.
The Run Flat Indicator Active Press
Run Flat Indicator Active Press
'OK' to Restart
'OK' to Restart message appears in the
multifunction display.
If you wish to confirm the restart:
X Press the 0076button.
The Tire Pressure Now OK?
Tire Pressure Now OK? message
appears in the multifunction display.
X Press the 0063or0064 button to select Yes
Yes.
X Press the 0076button.
The Run Flat Indicator Restarted
Run Flat Indicator Restarted mes-
sage appears in the multifunction display.
After a teach-in period, the tire pressure loss
warning system will monitor the set tire pres-
sures of all four tires.
If you wish to cancel the restart: X Press the 0038button.
or
X When the Tire TirePressure
Pressure Now
NowOK?
OK?message
appears, press the 0063or0064 button to
select Cancel
Cancel .
X Press the 0076button.
The tire pressure values stored at the last
restart will continue to be monitored. Tire pressure monitor
General notes If a tire pressure monitor is installed, the vehi-
cle's wheels have sensors that monitor the tire
pressures in all four tires. The tire pressure mon-
itor warns you if the pressure drops in one or
more of the tires. The tire pressure monitor only functions if the corresponding sensors are
installed in all wheels. Tire pressure
359Wheels and tires Z

Information on tire pressures is displayed in the
multifunction display. After a few minutes of
driving, the current tire pressure of each tire is
shown in the Serv.
Serv. menu of the multifunction
display, see illustration (example). For information on the message display, refer to
the "Checking the tire pressure electronically"
section (Y page 361).
Important safety notes G
WARNING
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 Infor-
mation 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 monitoring system (TPMS) that illuminates a low tire pres-
sure telltale when one or more of your tires
are significantly underinflated. Accordingly,
when the low tire pressure telltale illuminates,
you should stop and check your tires as soon
as possible, and inflate them to the proper
pressure. Driving on a significantly underin-
flated tire causes the tire to overheat and can lead to tire failure. Underinflation also
reduces fuel efficiency and tire tread life, andmay affect the vehicle's handling and stop-
ping ability.
Please note that the TPMS is not a substitute
for proper tire maintenance, and it is the driv-
er's responsibility to maintain correct tire pressure, even if underinflation has not
reached the level to trigger illumination of the TPMS low tire pressure telltale.
USA only:
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 vehi-
cle is started as long as the malfunction
exists.
When the malfunction indicator is illuminated,
the system may not be able to detect or signal low tire pressure as intended. TPMS malfunc-tions may occur for a variety of reasons,
including the mounting of incompatible
replacement or alternate tires or wheels on
the vehicle that prevent the TPMS from func-
tioning properly. Always check the TPMS mal-
function 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 prop-
erly.
It is the driver's responsibility to set the tire
pressure to that recommended for cold tires
which is suitable for the operating situation
(Y page 355). Note that the correct tire pressure
for the current operating situation must first be
taught-in to the tire pressure monitor. If a sub-
stantial loss of pressure occurs, the warning
threshold for the warning message is aligned to the taught-in reference values. Restart the tire
pressure monitor after adjusting the pressure of
the cold tires (Y page 362). The current pres-
sures are saved as new reference values. As a
result, a warning message will appear if the tire
pressure drops significantly.
The tire pressure monitor does not warn you of
an incorrectly set tire pressure. Observe the
notes on the recommended tire pressure
(Y page 355).
The tire pressure monitor is not able to warn you of a sudden loss of pressure, e.g. if the tire is
penetrated by a foreign object. In the event of a 360
Tire pressureWheels and tires

All about wheels and tires
Uniform Tire Quality Grading Stand-
ards
Overview of Tire Quality Grading Stand- ards 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 fac-
tors: 0043tread wear grade, 0044traction grade and
0087 temperature grade. These regulations do not
apply to Canada. Nevertheless, all tires sold in
North America are provided with the corre-
sponding quality grading markings on the side-
wall of the tire.
Quality grades can be found, where applicable,
on the tire sidewall between tread shoulder and
maximum section width.
Example:
R Treadwear grade: 200
R Traction grade: AA
R Temperature grade: A
All passenger car tires must conform to the stat-
utory safety requirements in addition to these
grades.
i The actual values for tires are vehicle-spe-
cific and may deviate from the values in the
illustration.
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 cli-
mate.
Traction G
WARNING
The traction grade assigned to this tire is
based on straight-ahead braking traction
tests, and does not include acceleration, cor- nering, hydroplaning, or peak traction char-
acteristics.
! Avoid wheelspin. This can lead to damage to
the drive train.
The traction grades – from highest to lowest –
are AA, A, B and C. Those grades represent the
tire's ability to stop on wet pavement as meas-
ured under controlled conditions on specified
government test surfaces of asphalt and con-
crete. A tire 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 condi-
tions when temperatures are around freezing
point.
Mercedes-Benz recommends a minimum tread
depth of 00CFin (4 mm) on all four winter tires.
Observe the legally required minimum tire tread
depth (Y page 353). Winter tires can reduce the
braking distance on snow-covered surfaces in
comparison with summer tires. The braking dis-
tance is still much further than on surfaces that
are not icy or covered with snow. Take appro-
priate care when driving.
Further information on winter tires (M+S tires)
(Y page 354).
Temperature G
WARNING
The temperature grade for this tire is estab-
lished for a tire that is properly inflated and
not overloaded. Excessive speed, underinfla-
tion, or excessive loading, either separately or 366
All about wheels and tiresWheels and ti
res

PSI (pounds per square inch)
A standard 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:
R if the vehicle has been parked with the tires
out of direct sunlight for at least three hours
and
R if the vehicle has not been driven further than
1 mile (1.6 km)
Tread
The part of the tire that comes into contact with
the road.
BeadThe 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, a roof rack or a high-per-
formance battery, are not included in the curb
weight and the weight of the accessories.
TIN (Tire Identification Number) This is a unique identifier which can be used by
a tire manufacturer to identify tires, for example for a product 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 a code that contains the maximum load bearing capa-
city of a tire.
Traction
Traction is the result of friction between the tires and the road surface.
TWR (Tongue Weight Rating)
The TWR specifies the maximum permissible
weight that the ball coupling of the trailer tow
hitch can support.
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 00CDin (1.6 mm)
has been reached.
Occupant distribution
The distribution of occupants in a vehicle at their designated seating positions.
Total load limit Nominal load and luggage load plus 68 kg
(150 lbs) multiplied by the number of seats in
the vehicle. Changing a wheel
Flat tire
The "Breakdown assistance" section
(Y page 335) contains information and notes on
how to deal with a flat tire. Information on driv-
ing with MOExtended tires in the event of a flat
tire can be found under "MOExtended tires (tires with run-flat characteristics" (Y page 336).
Vehicles with an emergency spare wheel: in
the event of a flat tire, mount the emergency
spare wheel according to the description under "Mounting a wheel" (Y page 373). Rotating the wheels
G
WARNING
Rotating the front and rear wheels if the
wheels or tires have different dimensions may severely impair the driving characteristics.
The service brake or wheel suspension com- 372
Changing a wheelWheels and tires