347 Operation
Tires and wheels
Summer tires
At the tire manufacturer’s option, any
tire with a speed capability above
149 mph (240 km/h) can include a
“ZR” in the size designation (for exam-
ple: 245/40 ZR18). To determine the
maximum speed capability of the tire,
the service description for the tire must
be referred to. The service description is comprised of the tire load rating5
(
page 344) and the tire speed
rating6 (
page 344).
If your tire includes “ZR” in the size
designation and no service
description5 and6 (
page 344) is
given, the tire manufacturer must be
consulted for the maximum speed ca-
pability.
If a service description5 and6
(
page 344) is given, the speed capa-
bility is limited by the speed symbol in
the service description.
Example: 245/40 ZR18 97Y.
In this example, “97Y” is the service
description. The letter “Y” designates
the speed rating and the speed capabil-
ity of the tire is limited to 186 mph
(300 km/h).
Any tire with a speed capability above
186 mph (300 km/h) must include a
“ZR” in the size designation AND the
service description must be placed in
parenthesis. Example: 275/40 ZR 18
(99Y). The “(Y)” speed rating in paren-
thesis designates the maximum speed
capability of the tire as being above
186 mph (300 km/h). Consult the tire
manufacturer for the actual maximum
permissible speed of the tire.
Index
Speed rating
Q
up to 100 mph (160 km/h)
R
up to 106 mph (170 km/h)
S
up to 112 mph (180 km/h)
T
up to 118 mph (190 km/h)
H
up to 130 mph (210 km/h)
V
up to 149 mph (240 km/h)
W
up to 168 mph (270 km/h)
Y
up to 186 mph (300 km/h)
(Y)
above 186 mph (300 km/h)
ZR
above 149 mph (240 km/h)
349 Operation
Tires and wheels
DOT, Tire Identification Number (TIN)
U.S. tire regulations require each new tire
manufacturer or tire retreader to mold a
TIN into or onto a sidewall of each tire
produced.
The TIN is a unique identifier which facili-
tates efforts by tire manufactures to notify
purchasers in recall situations or other
safety matters concerning tires and gives
purchasers the means to easily identify
such tires.
The TIN is comprised of “Manufacturer’s
identification mark”, “Tire size”, “Tire type
code” and “Date of manufacture”.1DOT
2Manufacturer’s identification mark
3Tire size
4Tire type code (at the option of the tire
manufacturer)
5Date of manufactureDOT (D
epartment o
f T
ransportation)
A tire branding symbol1 (
page 349)
which denotes the tire meets require-
ments of the U.S. Department of Transpor-
tation.
Manufacturer’s identification mark
The manufacturer’s identification mark2
(
page 349) denotes the tire
manufacturer.
New tires have a mark with two symbols.
Retreaded tires have a mark with four sym-
bols. For more information on retreaded
tires, see (
page 328).
Tire size
The code3 (page 349) indicates the
tire size.
iFor illustration purposes only. Actual
data on tires are specific to each vehi-
cle and may vary from data shown in
above illustration.
355 Operation
Tires and wheels
Maximum tire inflation pressure
This number is the greatest amount of air
pressure that should ever be put in the tire
under normal driving conditions.
Normal occupant weight
The number of occupants the vehicle is
designed to seat, multiplied by
68 kilograms (150 lbs).
Occupant distribution
The distribution of occupants in a vehicle
at their designated seating positions.
Production options weight
The combined weight of those installed
regular production options weighing over
5 lbs (2.3 kilograms) in excess of those
standard items which they replace, not
previously considered in curb weight or
accessory weight, including heavy duty
brakes, ride levelers, roof rack, heavy duty
battery, and special trim.PSI (P
ounds per s
quare i
nch)
A standard unit of measure for air pressure
-> bar, kilopascal (kPa).
Recommended tire inflation pressure
Recommended tire inflation pressure
listed on placard located on driver’s door
B-pillar for normal driving conditions.
Provides best handling, tread life and
riding comfort.
Rim
A metal support for a tire or a tire and tube
assembly upon which the tire beads are
seated.
Sidewall
The portion of a tire between the tread and
the bead.TIN (T
ire I
dentification N
umber)
Unique identifier which facilitates efforts
by tire manufacturers to notify purchasers
in recall situations or other safety matters
concerning tires and gives purchases the
means to easily identify such tires. The TIN
is comprised of “Manufacturer’s identifica-
tion mark”, “Tire size”, “Tire type code”
and “Date of manufacture”.
Tire load rating
Numerical code associated with the
maximum load a tire can support.
Tire ply composition and material used
This indicates the number of plies or the
number of layers of rubber-coated fabric in
the tire tread and sidewall. Tire manufac-
turers also must indicate the ply materials
in the tire and sidewall, which include
steel, nylon, polyester, and others.
356 OperationTires and wheelsTire speed rating
Part of tire designation; indicates the
speed range for which a tire is approved.
Traction
Force exerted by the vehicle on the road
via the tires. The amount of grip provided.
Tread
The portion of a tire that comes into
contact with the road.
Treadwear indicators
Narrow bands, sometimes called
“wear bars” that show across the tread of
a tire when only
1/16
in (1.6 mm) of tread
remains.Uniform Tire Quality Grading Standards
A tire information system that provides
consumers with ratings for a tire’s traction,
temperature and treadwear. Ratings are
determined by tire manufacturers using
government testing procedures. The
ratings are molded into the sidewall of the
tire.
Vehicle capacity weight
Rated cargo and luggage load plus
68 kilograms (150 lbs) times the vehicle’s
designated seating capacity.
Vehicle maximum load on the tire
Load on an individual tire that is
determined by distributing to each axle its
share of the maximum loaded vehicle
weight and dividing it by two.
Rotating tires
Tire rotation can be performed on vehicles
with tires of the same dimension all
around. If your vehicle is equipped with
tires of the same dimension all around,
tires can be rotated, observing a
front-to-rear rotation pattern that will
maintain the intended rotation (spinning)
direction of the tire (
page 331).
In some cases, such as when your vehicle
is equipped with mixed-size tires (different
tire dimension front vs. rear), tire rotation
is not possible.
Warning!
G
Rotate front and rear wheels only if the tires
are of the same dimension.
If your vehicle is equipped with mixed-size
tires (different tire dimensions front vs.
rear), tire rotation is not possible.
359 Operation
Winter driving
Block heater* (Canada only)
The engine is equipped with a block heat-
er.
The electrical cable may be installed at an
authorized Mercedes-Benz Center.Snow chains
Snow chains should only be driven on
snow-covered roads at speeds not to ex-
ceed 30 mph (50 km/h). Remove chains
as soon as possible when driving on roads
without snow.Please observe the following guidelines
when using snow chains:
Use of snow chains is not permissible
with all wheel/tire combinations.
Snow chains should only be used on
the rear wheels. Follow the manufac-
turer’s mounting instructions.
Only use snow chains that are ap-
proved by Mercedes-Benz. Your autho-
rized Mercedes-Benz Center will be
glad to advise you on this subject.
Use of snow chains may be prohibited
depending on location. Always check
local and state laws before installing
snow chains.
Have the spare tire replaced with a winter
tire at the nearest authorized
Mercedes-Benz Center.!When driving with snow chains, always
select the raised level of the level con-
trol system Airmatic* (
page 260).
Other settings may result in damage to
your vehicle.
iWhen driving with snow chains, you
may wish to deactivate the ESP
®
(
page 96) before setting the vehicle
in motion. This will improve the vehi-
cle’s traction.
!Even on vehicles with all-wheel-drive,
use snow chains on rear tires only.
Some tire sizes do not leave adequate
clearance for snow chains. To help
avoid serious damage to your vehicle or
tires, use of snow chains is not permis-
sible with the following tire sizes:
265/35 ZR18 XL (Extra Load)
T 155/70 R17 110 M
T 175/55-18 95 P
382 Practical hintsWhat to do if …Warning!
G
Each tire, including the spare (if provided),
should be checked monthly when cold and
inflated to the inflation pressure recom-
mended by the vehicle manufacturer on the
vehicle placard or the tire inflation pressure
label. (If your vehicle has tires of a different
size than the size indicated on the vehicle
placard or the tire inflation pressure label,
you should determine the proper tire infla-
tion 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 is significantly under-inflated. 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 significant-
ly under-inflated tire causes the tire to over-
heat and can lead to tire failure.
Under-inflation also reduces fuel efficiency
and tire tread life, and may affect the vehi-
cle’s handling and stopping 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 under-inflation 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
when the system is not operating properly.
The TPMS malfunction indicator is com-
bined with the low tire pressure telltale.
When the system detects a malfunction, the
telltale will flash for approximately
one minute and then remain continuously
illuminated. This sequence will continue
upon subsequent vehicle start-ups as long
as the malfunction exists. When the mal-
function indicator is illuminated, the system
may not be able to detect or signal low tire
pressure as intended.
TPMS malfunctions may occur for a variety
of reasons, including the installation of in-
compatible 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.
442 Practical hintsFlat tirePreparing the vehicle
Prepare the vehicle as described
(page 441).
Vehicles with Minispare wheel
(except E 55 AMG):
Take the Minispare wheel, wheel
wrench and the jack out of the trunk
(page 422).
Vehicles with collapsible tire
(E 55 AMG only):
Take the collapsible tire, wheel wrench,
jack and electric air pump out of the
cargo compartment (
page 422).Lifting the vehicle
Prevent the vehicle from rolling away
by blocking wheels with wheel chocks
or other sizable objects.
One wheel chock is included with the
vehicle tool kit (
page 424).
When changing wheel on a level surface:
Place the wheel chock in front of and
another sizable object behind the
wheel that is diagonally opposite to the
wheel being changed.
Always try lifting the vehicle using the jack
on a level surface. However, should
circumstances require you to do so on a
hill, place the wheel chock and the other
sizeable object as follows:
Place the wheel chock and another siz-
able object on the downhill side block-
ing both wheels of the axle not being
worked on.
Warning!
G
The jack is designed exclusively for jacking
up the vehicle at the jack take-up brackets
built into either side of the vehicle. To help
avoid personal injury, use the jack only to lift
the vehicle during a wheel change. Never
get beneath the vehicle while it is supported
by the jack. Keep hands and feet away from
the area under the lifted vehicle. Always
firmly set parking brake and block wheels
before raising vehicle with jack.
Do not disengage parking brake while the
vehicle is raised. Be certain that the jack is
always vertical (plumb line) when in use, es-
pecially on hills. Always try to use the jack
on level surface. Be sure that the jack arm is
fully seated in the jack take-up bracket. Al-
ways lower the vehicle onto sufficient ca-
pacity jackstands before working under the
vehicle.
448 Practical hintsFlat tireMOExtended system*
The MOExtended system allows you to
continue driving your vehicle even if there
is a total loss of pressure in one or more
tires.
You may only use the MOExtended system
with the Tire Pressure Monitoring System*
(TPMS*) (
page 339).
!The maximum distance in emergency
mode depends on the vehicle’s load. It
is 30 miles (50 km) if the vehicle is par-
tially loaded and 18 miles (30 km) if the
vehicle is fully loaded.
The point at which the maximum driv-
ing distance begins in emergency
mode is when the warning message
appears in the multifunction display
indicating that there is a loss of tire
inflation pressure.
Do not exceed the maximum speed of
50 mph (80 km/h).
Warning!
G
In emergency mode, your vehicle’s driving
characteristics are diminished in such situa-
tions as:
driving around curves
while braking
while accelerating rapidly
Therefore, your driving style must be adapt-
ed accordingly. Avoid abrupt steering and
driving maneuvers, as well as driving over
obstacles (road curbs, potholes, or off-road
areas). This is especially important if the ve-
hicle is heavily loaded.
The emergency driving distance that can be
achieved greatly depends on the demands
placed on the vehicle. Depending on speed,
load, driving maneuvers, road conditions,
outside temperature, etc., the distance can
be significantly shorter or, if the vehicle is
driven cautiously, somewhat longer.
Do not continue driving in emergency mode
if
you notice knocking sounds
the vehicle starts to shake
smoke develops and you smell rubber
ESP
® is intervening continuously
you notice tears on the tire sidewalls
After driving in emergency mode, you must
have the rims inspected by an authorized
Mercedes-Benz Center to check if they are
suitable for further use. The failed tire must
be replaced in any case.iWhen replacing individual or all tires on
the vehicle, make sure only matching
tires marked with “MOExtended” are
mounted in the size specified for your
vehicle.