when adjusting the tire pressure
(Y
page 376).
i The actual values for tires are vehicle-
specific and may deviate from the values in
the illustration. Checking the tire pressures
Important safety notes Observe the notes on tire pressure
(Y
page 376).
Information on air pressure for the tires on
your vehicle can be found:
R on the vehicle's Tire and Loading
Information placard on the B-pillar
(Y page 383)
R on the tire pressure label on the fuel filler
flap ( Ypage 176)
R in the "Tire pressure" section
R under "Tire pressure" (Y page 376)
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 gauge securely onto
the valve.
X Read the tire pressure and compare it with
the recommended value on the Tire and
Loading Information placard (Y page 376).
X If the tire pressure is too low, increase it to
the recommended value.
X If the tire pressure is too high, release air
by pressing down the metal pin in the valve.
Use the tip of a pen, for example. Then,
check the tire pressure again using the tire
pressure gauge.
X Screw the valve cap onto the valve.
X Repeat these steps for the other tires. Tire pressure loss warning system
(Canada only)
General notes While the vehicle is in motion, the tire
pressure loss warning system monitors the
set tire pressure 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, a corresponding warning
message will appear in the multifunction
display.
You can recognize the tire pressure loss
warning by the Run Flat Indicator Run Flat Indicator
Active Press 'OK' to Restart
Active Press 'OK' to Restart message
which appears in the Service
Servicemenu of the
multifunction display. Information on the
message display can be found in the
"Restarting the tire pressure loss warning
system" section (Y page 380).
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 376).
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 pressure 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 maneuvers.
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. Tire pressure
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Curb weight
The weight of a vehicle with standard
equipment including the maximum capacity
of fuel, oil and coolant. It also includes the air-
conditioning system and optional equipment
if these are installed in the vehicle, but does
not include passengers or luggage.
Maximum load rating
The maximum tire load is the maximum
permissible weight in kilograms or lbs for
which a tire is approved.
Maximum permissible tire pressure
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.
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
outward force to each square inch of the tire's
surface. 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 without
direct sunlight on the tires for at least three
hours and
R if the vehicle has been driven for less than
1 mile (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 kilograms (5 lbs).
These optional extras, such as high-
performance brakes, level control, a roof rack
or a high-performance 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 purchasers. The TIN is made up of the
manufacturer'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
capacity of a tire.
Traction
Traction is the result of friction between the
tires and the road surface.
Treadwear indicators
Narrow bars (tread wear bars) that are
distributed over the tire tread. If the tire tread
is level with the bars, the wear limit of áin
(1.6 mm) has been reached. 394
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Components damaged in this way may fail
unexpectedly. There is a risk of an accident.
Do not use power washers with circular jet
nozzles to clean the vehicle. Have damaged
tires or chassis components replaced
immediately. Mounting a wheel
Preparing the vehicle X
Stop the vehicle on solid, non-slippery and
level ground.
X Apply the parking brake.
X Bring the front wheels into the straight-
ahead position.
X Shift the transmission to position P.
X Vehicles with AIRMATIC: make sure that
"normal" level is selected (Y page 204).
X Switch off the engine.
X Vehicles without KEYLESS-GO: remove
the SmartKey from the ignition lock.
X Vehicles with 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.
X Vehicles with KEYLESS-GO: remove the
Start/Stop button from the ignition lock
(Y page 159).
X If included in the vehicle equipment,
remove the tire-change tool kit from the
vehicle (Y page 352).
X Secure the vehicle to prevent it from rolling
away. Securing the vehicle to prevent it from
rolling away If your vehicle is equipped with a wheel chock,
it can be found in the tire-change tool kit
(Y
page 352).
The folding wheel chock is an additional
safety measure to prevent the vehicle from
rolling away, for example when changing a
wheel.
X Fold both plates upwards :.
X Fold out lower plate ;.
X Guide the lugs on the lower plate fully into
the openings in base plate =. Securing the vehicle on level ground (example:
Sedan)
X
On level ground: place chocks or other
suitable items under the front and rear of
the wheel that is diagonally opposite the
wheel you wish to change. 396
Changing a wheelWheels and tires
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Securing the vehicle on slight downhill gradients
(example: Sedan)
X On light downhill gradients: place
chocks or other suitable items in front of
the wheels of the front and rear axle.
Raising the vehicle G
WARNING
If you do not position the jack correctly at the
appropriate jacking point of the vehicle, the
jack could tip over with the vehicle raised.
There is a risk of injury.
Only position the jack at the appropriate
jacking point of the vehicle. The base of the
jack must be positioned vertically, directly
under the jacking point of the vehicle.
! The jack is designed exclusively for
jacking up the vehicle at the jacking points.
Otherwise, your vehicle could be damaged.
Observe the following when raising the
vehicle:
R to raise the vehicle, only use the vehicle-
specific jack that has been tested and
approved by Mercedes-Benz. If used
incorrectly, the jack could tip over with the
vehicle raised.
R the jack is designed only to raise and hold
the vehicle for a short time while a wheel
is being changed. It is not suited for
performing maintenance work under the
vehicle.
R avoid changing the wheel on uphill and
downhill slopes. R
before raising the vehicle, secure it from
rolling away by applying the parking brake
and inserting wheel chocks. Never
disengage the parking brake while the
vehicle is raised.
R the jack must be placed on a firm, flat and
non-slip surface. On a loose surface, a
large, load-bearing underlay must be used.
On a slippery surface, a non-slip underlay
must be used, e.g. rubber mats.
R do not use wooden blocks or similar
objects as a jack underlay. Otherwise, the
jack will not be able to achieve its load-
bearing capacity due to the restricted
height.
R make sure that the distance between the
underside of the tires and the ground does
not exceed 1.2 in (3 cm).
R never place your hands and feet under the
raised vehicle.
R never lie under the raised vehicle.
R never start the engine when the vehicle is
raised.
R never open or close a door or the trunk lid/
tailgate when the vehicle is raised.
R make sure that no persons are present in
the vehicle when the vehicle is raised.
AMG vehicles with Performance Studio
equipment: the wheel bolts are covered by a
hub cap. Before you are able to unscrew the
wheel bolts, you must first remove the hub
cap. Changing a wheel
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X
To remove: turn the center cover of hub
cap :counter-clockwise and remove.
X To install: before installing, ensure that
hub cap :is in the open position. To do
so, turn the center cover counter-
clockwise.
X Place hub cap :in position and turn the
center cover clockwise until you feel and
hear hub cap :engage.
X Make sure that hub cap :is installed
securely. X
Using lug wrench ;, loosen the bolts on
the wheel you wish to change by about one
full turn. Do not unscrew the bolts
completely. Jacking points (example: Sedan)
The jacking points are located just behind the
front wheel housings and just in front of the
rear wheel housings (arrows).
AMG vehicles and vehicles with AMG
equipment: the vehicle has covers installed
next to the jacking points on the outer sills to
protect the vehicle body. Cover, front (example: vehicles with AMG Sports
package)
X
AMG vehicles and vehicles with AMG
equipment: fold cover=upwards. X
Position jack Aat jacking point ?. Example
X
Make sure the foot of the jack is directly
beneath the jacking point. 398
Changing a wheelWheels and tires
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X
Turn crank Bclockwise until jack Asits
completely on jacking point ?and the
base of the jack lies evenly on the ground.
X Turn crank Buntil the tire is raised a
maximum of 1.2 in (3 cm) off the ground.
Removing a wheel !
AMG vehicles: during removal and
repositioning of the wheel, the wheel rim
can strike the ceramic-brake disc and
damage it. Therefore, take precautions and
get a second person to assist you.
Alternatively, you can use a second
alignment bolt.
! Do not place wheel bolts in sand or on a
dirty surface. The bolt and wheel hub
threads could otherwise be damaged when
you screw them in. X
Unscrew the uppermost wheel bolt
completely.
X Screw alignment bolt :into the thread
instead of the wheel bolt.
X Unscrew the remaining wheel bolts fully.
X Remove the wheel.
Mounting a new wheel G
WARNING
Oiled or greased wheel bolts or damaged
wheel bolts/hub threads can cause the wheel
bolts to come loose. As a result, you could
lose a wheel while driving. There is a risk of
accident. Never oil or grease wheel bolts. In the event
of damage to the threads, contact a qualified
specialist workshop immediately. Have the
damaged wheel bolts or hub threads
replaced/renewed. Do not continue driving.
G
WARNING
If you tighten the wheel bolts or wheel nuts
when the vehicle is raised, the jack could tip
over. There is a risk of injury.
Only tighten the wheel bolts or wheel nuts
when the vehicle is on the ground.
Always pay attention to the instructions and
safety notes in the "Changing a wheel"
section (Y page 395).
Only use wheel bolts that have been designed
for the wheel and the vehicle. For safety
reasons, Mercedes-Benz recommends that
you only use wheel bolts which have been
approved for Mercedes-Benz vehicles and the
respective wheel.
! AMG vehicles: during removal and
repositioning of the wheel, the wheel rim
can strike the ceramic-brake disc and
damage it. Therefore, take precautions and
get a second person to assist you.
Alternatively, you can use a second
alignment bolt.
! To prevent damage to the paintwork, hold
the wheel securely against the wheel hub
while screwing in the first wheel bolt. Positioning a wheel (example: vehicle with an
emergency spare wheel) Changing a wheel
399Wheels and tires Z
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