576 Operation
Tires and wheels
Tire and loading terminology
Accessory weight
The combined weight (in excess of those
standard items which may be replaced) of
automatic transmission, power steering,
power brakes, power windows, power
seats, radio, and heater, to the extent that
these items are available as
factory-installed equipment (whether
installed or not).
Air pressure
The amount of air inside the tire pressing
outward on each square inch of the tire.
Air pressure is expressed in pounds per
square inch (psi), or kilopascal (kPa) or
bars.
Aspect ratio
Dimensional relationship between tire
section height and section width
expressed in percentage.Bar
Another metric unit for air pressure. There
are 14.5038 pounds per square inch (psi)
to 1 bar; there are 100 kilopascals (kPa)
to 1 bar.
Bead
The tire bead contains steel wires wrapped
by steel cords that hold the tire onto the
rim.
Cold tire inflation pressure
Tire inflation pressure when your vehicle
has been sitting for at least 3 hours or driv-
en no more than 1 mile (1.6 km).
Curb weight
The weight of a motor vehicle with stan-
dard equipment including the maximum
capacity of fuel, oil, and coolant, and, if so
equipped, air conditioning and additional
optional equipment, but without passen-
gers and cargo.DOT (Department of Transportation)
A tire branding symbol which denotes the
tire meets requirements of the
U.S. Department of Transportation.
GAWR (G
ross Axle Weight Rating)
The GAWR is the maximum permissible
axle weight. The gross vehicle weight on
each axle must never exceed the GAWR for
the front and rear axle indicated on the
certification label located on the driver’s
door B-pillar.
GVW (G
ross Vehicle Weight)
The GVW comprises the weight of the
vehicle including fuel, tools, spare wheel,
installed accessories, passengers and
cargo and, if applicable, trailer tongue
load. The GVW must never exceed the
GVWR indicated on the certification label
located on the driver’s door B-pillar.
581 Operation
Winter driving
Snow chainsSnow chains should only be driven on
snow-covered roads at speeds not to
exceed 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
(
page 718).
Use snow chains in pairs and on rear
wheels only. Follow the manufacturer’s
mounting instructions.
Only use snow chains that are
approved by Mercedes-Benz. Any
authorized 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.
Do not use snow chains on the spare
wheel (
page 718).
Warning!G
If you use your spare tire when winter tires
are fitted on the other wheels, be aware that
the difference in tire characteristics may
very well impair turning stability and that
overall driving stability may be reduced.
Adapt your driving style accordingly.
Have the spare tire replaced with a winter
tire at the nearest authorized
Mercedes-Benz Center.
!When driving with snow chains, always se-
lect the raised level of the level control system
Airmatic (
page 440) or ABC* (page 443).
Other settings may result in damage to your
vehicle.
! 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, make sure that the use of
snow chains is permissible as specified in the
“Technical data” section of this Operator’s
Manual, see “Rims and tires” (
page 718).
! If snow chains are mounted to the front
wheels, they may scrape against the body or axle
components. The tires or the vehicle could be
damaged as a result.
iAll models except S 63 AMG:
When driving with snow chains, you may wish to
switch off the ESP
® (page 73) before setting
the vehicle in motion. This will improve the
vehicle’s traction.
iS 63 AMG:
Do not switch off the ESP® when driving in snow
or with snow chains mounted.
609 Practical hints
What 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.
USA only:
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
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.
666 Practical hints
What to do if …?
Display Possible cause/consequencePossible solution
Wheel sensor(s)
missingOne or more sensors malfunction (e.g. bat-
tery in one or more wheel sensor is empty).
One or more wheels without wheel sensors
mounted (e.g. spare tire).
No pressure value is shown on the multi-
function display for the tire in question.Have the Advanced TPMS* checked by an
authorized Mercedes-Benz Center.
Have the wheel sensors installed by an
authorized Mercedes-Benz Center.
The tire pressure for the respective tire is
shown in the multifunction display after a few
minutes driving.
Tire pressure
Please rectifyVehicles with Advanced TPMS*:
The pressure is too low in one or more tires.
Or the tire pressures of the individual
wheels differ too radically from one anoth-
er.Check and adjust tire inflation pressure as
required (
page 561).
686 Practical hints
Flat tire
Preparing the vehicle
Park the vehicle in a safe distance from
moving traffic on a hard, flat surface
when possible.
Turn on the hazard warning flasher
(
page 377).
Turn the steering wheel so that the
front wheels are in a straight ahead
position.
Shift the automatic transmission to
park positionP.
Engage the electronic parking brake.
Turn off the engine.
Have any passenger exit the vehicle at
a safe distance from the roadway.
Vehicles with SmartKey: Remove the
SmartKey from the starter switch.
Vehicles with KEYLESS-GO*: Open the
driver’s door (this puts the starter
switch in position0, same as with the
SmartKey removed from the starter
switch). The driver’s door then can be
closed again.
Remove the KEYLESS-GO*
start/stop button from the starter
switch.
Mounting the spare wheel
iOpen the door only when conditions are safe
to do so.
Warning!G
The dimensions of the spare wheel are dif-
ferent from those of the road wheels. As a
result, the vehicle handling characteristics
change when driving with a spare wheel
mounted. Adapt your driving style accord-
ingly.
The spare wheel is for temporary use only.
When driving with spare wheel mounted,
ensure proper tire inflation pressure and
do not exceed a vehicle speed
of 50 mph (80 km/h).
Contact the nearest Mercedes-Benz Center
as soon as possible to have the spare wheel
replaced with a regular road wheel.
Never operate the vehicle with more than
one spare wheel mounted.
Do not switch off the ESP
® when a spare
wheel is mounted.
687 Practical hints
Flat tire
Preparing the vehicle
Prepare the vehicle as described
(
page 686).
Take vehicle tool kit tray and vehicle
jack out of trunk (
page 668).
Take the spare wheel from the wheel
well under the trunk floor
(
page 670).
Lifting the vehicle
Prevent the vehicle from rolling away
by blocking wheels with wheel chocks
or other sizeable objects.
One wheel chock is included with the
vehicle tool kit (
page 670).
When changing wheel on a level surface:
Place the wheel chock in front of and
another sizeable 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 cir-
cumstances require you to do so on a hill,
place the wheel chock and another size-
able object as follows:
Place the wheel chock and another
sizeable object on the downhill side
blocking both wheels on the side of the
vehicle not being worked on.
Wheel wrench
On wheel to be changed, loosen but
do not yet remove the wheel bolts
(approximately one full turn with
wrench 1).
Warning!G
The jack is designed exclusively for jacking
up the vehicle at the jack take-up brackets
built into both sides 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 en-
gage the electronic parking brake and block
wheels before raising vehicle with jack.
Do not disengage electronic parking brake
while the vehicle is raised. Be certain that
the jack is always vertical (plumb line) when
in use, especially on hills. Always try to use
the jack on level surface.
Make sure the jack arm is fully seated in the
jack take-up bracket. Always lower the vehi-
cle onto sufficient capacity jackstands be-
fore working under the vehicle.
689 Practical hints
Flat tire
Removing the wheel
1Alignment bolt
Unscrew upper-most wheel bolt and
remove.
Replace this wheel bolt with alignment
bolt1 supplied in the tool kit.
Remove the remaining bolts.
Remove the wheel.Attaching the spare wheel
1Wheel bolt for light alloy rims and
Minispare wheel with light alloy rim
2Wheel bolt for Minispare wheel with
steel rim (located in trunk with spare
wheel)
!Do not place wheel bolts in sand or dirt. This
could result in damage to the bolt and wheel hub
threads.
Warning!G
Always replace wheel bolts that are dam-
aged or rusted.
Never apply oil or grease to wheel bolts.
Damaged wheel hub threads should be re-
paired immediately. Do not continue to drive
under these circumstances! Contact an au-
thorized Mercedes-Benz Center or call
Roadside Assistance.
Incorrect wheel bolts or improperly tight-
ened wheel bolts can cause the wheel to
come off. This could cause an accident.
Make sure you are using the correct wheel
bolts.
Warning!G
Only use Genuine Mercedes-Benz wheel
bolts. Other wheel bolts may come loose.
Do not tighten the wheel bolts when the ve-
hicle is raised. Otherwise the vehicle could
fall off the jack.
690 Practical hints
Flat tire
Clean contact surfaces of wheel and
wheel hub.
Guide the spare wheel onto the align-
ment bolt and push it on.
Insert wheel bolts and tighten them
slightly.
Unscrew the alignment bolt, install the
last wheel bolt and tighten slightly.Lowering the vehicle
Lower vehicle by turning crank coun-
terclockwise until vehicle is resting ful-
ly on its own weight.
Remove the jack.
1 - 5 Wheel bolts
!Wheel bolts2 must be used when mount-
ing a Minispare wheel with steel rim. The use of
any wheel bolts other than wheel bolts2 for a
Minispare wheel with steel rim will physically
damage the vehicle’s brakes.
Wheel bolts1 must be used when mounting a
Minispare wheel with light alloy rim. The use of
any wheel bolts other than wheel bolts1 for
a Minispare wheel with light alloy rim will physi-
cally damage the vehicle’s brakes.
Warning!G
Make sure to use the original length wheel
bolts when remounting the original wheel
after it has been repaired.!To avoid paint damage, place wheel flat
against hub and hold it there while installing first
wheel bolt.