2010 MERCEDES-BENZ R320 tires

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), kilopascal (kPa), or bar.
Aspect ratio
Dimensional relationship between tire
section height and section width expressed
in percentage.
Bar
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 driven no
more than 1 mile (1.6 km).
Curb weight
The weight of a motor vehicle with standard
equipment including the maximum capacity
of fuel, oil, and coolant, and, if so equipped,
air conditioning and additional optional
equipment, but without passengers and
cargo.
DOT (Department of Transportation)
A tire branding symbol which denotes the tire
meets requirements of the U.S. Department
of Transportation. GAWR (Gross 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.
GTW (Gross Trailer Weight) The GTW is the weight of the trailer plus the
weight of all cargo, equipment, luggage etc.
loaded on the trailer.
GVW (Gross 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.
GVWR (Gross Vehicle Weight Rating) This is the maximum permissible vehicle
weight of the fully loaded vehicle (weight of
the

vehicle including all options, passengers,
fuel, and cargo and, if applicable, trailer
tongue load). It is indicated on the
certification label located on the driver’s door
B-pillar.
Kilopascal (kPa) Metric unit for air pressure. There are 6.9 kPa
to 1 psi; another metric unit for air pressure
is bar. There are 100 kilopascals (kPa) to
1 bar.
Load index
Numerical code associated with the
maximum load a tire can support.
Maximum load rating
The maximum load in kilograms and pounds
that can be carried by the tire. Tires and wheels
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Maximum loaded vehicle weight
The sum of curb weight, accessory weight,
total load limit, and production options
weight.
Maximum permissible tire inflation
pressure
This number is the greatest amount of air
pressure that should ever be put in the tire.
Normal occupant weight
The number of occupants the vehicle is
designed to seat, multiplied by 68 kilograms
(150 lb).
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 (Pounds per square inch)
A standard unit of measure for air pressure.
Recommended tire inflation pressure
The recommended tire inflation pressure for
normal
driving conditions is listed on the Tire
and Loading Information placard located on
the driver’s door B-pillar. It provides best
handling, tread life and riding comfort.
Supplemental information pertaining to
special driving situations can be found on the
tire inflation pressure label on the inside of
the fuel filler flap. 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 (Tire Identification Number)
Unique identifier which facilitates efforts by
tire manufacturers 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”.
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
manufacturers also must indicate the ply
materials in the tire and sidewall, which
include steel, nylon, polyester, and others.
Tire speed rating
Part of tire designation (speed symbol);
indicates the speed range for which a tire is
approved.
Total load limit
Rated cargo and luggage load plus
68 kilograms (150 lb) times the vehicle’s
designated seating capacity.
Traction
The adhesive friction of a tire on a surface on
which

it moves. The amount of grip provided. 250
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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.
TWR (Tongue Weight Rating) Maximum permissible weight on trailer
tongue.
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 U.S.
government testing procedures. The ratings
are molded into the sidewall of the tire.
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. Winter driving
General information
Have
your vehicle winterized at an authorized
Mercedes-Benz Center.
i Vehicles with diesel engine:
Do not cover the radiator, for example with
a winter front. Otherwise the readings of
the on-board diagnostic system may be
inaccurate. Some of theses readings are
required by law and must be accurate at all
times. Winter tires
G
Warning!
Winter tires with a tread depth of less than
1 / 6 in (4 mm) must be replaced. They are no
longer suitable for winter operation. G
Warning!
If you use your spare wheel 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 wheel replaced by a regular
road wheel with a winter tire at the nearest
authorized Mercedes-Benz Center.
Always use winter tires at temperatures
below 45‡ (7†) and whenever wintry road
conditions prevail. Not all M+S rated tires
provide special winter performance. Make
sure the tires you use show the mountain/
snowflakeimarking on the tire sidewall.
These tires meet specific snow traction
performance requirements of the Rubber
Manufacturers Association (RMA) and the
Rubber Association of Canada (RAC) and
have been designed specifically for use in
snow conditions. Use of winter tires is the
only way to achieve the maximum
effectiveness of your vehicle’s driving safety
systems such as the ABS and the ESP ®
in
winter operation.
For safe handling, make sure all mounted
winter tires are of the same make and have
the same tread design.
For information on winter tires for your
vehicle model, see the “Technical data”
section ( Y page 347).
Always observe the speed rating of the winter
tires installed on your vehicle. Winter driving
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Snow chains
! Vehicles with Adaptive Damping System
(ADS):
When driving with snow chains, do not
select SPORT mode as this may result in
damage to your vehicle.
! Some tire sizes do not leave adequate
clearance for snow chains. To help avoid
serious damage to your vehicle or tires,
make sure the use of snow chains is
permissible as specified in the “Technical
data” section of this Operator’s Manual.
Snow 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.
Observe the following guidelines when using
snow chains:
R Use of snow chains is not permissible with
all wheel/tire combinations ( Y page 347).
R Use snow chains in pairs and on rear
wheels only. Follow the manufacturer’s
mounting instructions.
! 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.
R Only use snow chains that are approved by
Mercedes-Benz. Any authorized Mercedes-
Benz Center will be glad to advise you on
this subject.
R Use of snow chains may be prohibited
depending on location. Always check local
and state laws before installing snow
chains.
R Do not use snow chains on the spare wheel.
i When driving with snow chains, you may
wish to switch off the ESP ®
(Y page 65)
before setting the vehicle in motion. This
will improve the vehicle’s traction. Winter driving instructions
G
Warning!
If the vehicle becomes stuck in snow, make
sure snow is kept clear of the exhaust pipe
and from around the vehicle with the engine
running. Otherwise, deadly carbon monoxide
(CO) gases may enter vehicle interior
resulting in unconsciousness and death.
To

assure sufficient fresh air ventilation, open
a window slightly on the side of the vehicle
not facing the wind. G
Warning!
The outside temperature indicator is not
designed to serve as an ice-warning device
and is therefore unsuitable for that purpose.
Indicated temperatures just above the
freezing

point do not guarantee that the road
surface is free of ice. The road may still be icy,
especially in wooded areas or on bridges. G
Warning!
On slippery road surfaces, never downshift in
order to obtain braking action. This could
result

in drive wheel slip and reduced vehicle
control. Your vehicle’s ABS will not prevent
this type of loss of control.
The most important rule for slippery or icy
roads is to drive sensibly and to avoid abrupt
acceleration, braking and steering
maneuvers. Do not use the cruise control
system under such conditions.
When the vehicle is in danger of skidding, shift
the automatic transmission to neutral
position N. Try to keep the vehicle under
control by corrective steering action.
i For information on driving with snow
chains, see “Snow chains” ( Y page 252).
Road salts and chemicals can adversely
affect braking efficiency. Increased pedal
force may become necessary to produce the
normal brake effect.
Depressing the brake pedal periodically when
traveling at length on salt-strewn roads can 252
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bring road-salt-impaired braking efficiency
back to normal.
If the vehicle is parked after being driven on
salt-treated roads, the braking efficiency
should be tested as soon as possible after
driving is resumed.
G
Warning!
Make sure not to endanger any other road
users when carrying out these braking
maneuvers. Driving instructions
Drive sensibly – save fuel
To save fuel you should:
R Keep tires at the recommended inflation
pressures.
R Remove unnecessary loads.
R Remove carriers when not in use.
R Allow engine to warm up under low load
use.
R Avoid frequent acceleration and
deceleration.
R Have all maintenance work performed at
the intervals specified in the Maintenance
Booklet and as required by the
Maintenance system. Contact an
authorized Mercedes-Benz Center.
Fuel
consumption is also increased by driving
in cold weather, in stop-and-go traffic, on
short trips and in mountainous areas. Drinking and driving
G
Warning!
Drinking and driving and/or taking drugs and
driving are very dangerous combinations.
Even a small amount of alcohol or drugs can
affect your reflexes, perceptions and
judgment. The possibility of a serious or even fatal
accident

are greatly increased when you drink
or take drugs and drive.
Do not drink or take drugs and drive or allow
anyone to drive who has been drinking or
taking drugs. Pedals
G
Warning!
Make sure absolutely no objects are
obstructing the pedals’ range of movement.
Keep the driver’s footwell clear of all
obstacles. If there are any floormats or
carpets in the footwell, make sure that the
pedals still have sufficient clearance.
During sudden driving or braking maneuvers,
the objects could get caught between the
pedals. You could then no longer brake or
accelerate. This could lead to accidents and
injury. Power assistance
G
Warning!
There is no power assistance for the steering
and
the brake when the engine is not running.
Steering and braking requires significantly
more effort and you could lose control of the
vehicle and cause an accident as a result.
Do not turn off the engine while the vehicle is
in motion. Brakes
Downhill grades !
When driving down long and steep
grades, relieve the load on the brakes by
shifting into a lower gear to use the
engine’s

braking power. This helps prevent
overheating of the brakes and reduces
wear. Driving instructions
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!
Only conduct operational or performance
tests on a two-axle dynamometer. If such
tests are necessary, contact an authorized
Mercedes-Benz Center. You could
otherwise seriously damage the brake
system or the transfer case which is not
covered by the Mercedes-Benz Limited
Warranty.
! Because the ESP ®
operates
automatically, the engine and ignition must
be shut off (SmartKey in starter switch
position 0 or 1 or KEYLESS-GO start/stop
button in position 0 or 1) when the parking
brake is being tested on a brake test
dynamometer. Such testing should be no
longer than 10 seconds.
Active braking action through the ESP ®
may otherwise seriously damage the brake
system which is not covered by the
Mercedes-Benz Limited Warranty.
If your brake system is only subjected to
moderate loads, you should occasionally test
the effectiveness of the brakes by applying
above-normal braking pressure at higher
speeds. This will also enhance the grip of the
brake pads. G
Warning!
Make sure not to endanger any other road
users when carrying out these braking
maneuvers.
Refer to the description of the Brake Assist
System (BAS) ( Y page 64).
Parking brake When driving on wet roads or dirt covered
surfaces, road salt and/or dirt can get into
the parking brake. To prevent corrosion and a reduction in the
braking power of the parking brake, observe
the following:
X
From time to time, lightly engage the
parking brake before driving off.
X Drive a distance of approximately 110 yds
(100 m) at a maximum speed of 12 mph
(20 km/h). G
Warning!
While performing this procedure please
assure that the vehicle is stopped before
applying the parking brake. Otherwise the
rear wheels could lock up. You could lose
control of the vehicle and cause an accident.
In addition, the vehicle’s brake lights do not
light up when the parking brake is engaged.
Make sure not to endanger any other road
users when you engage the parking brake. Driving off
Warm up the engine smoothly. Do not place
full load on the engine until the operating
temperature has been reached.
! When

driving off on a slippery surface, do
not allow a drive wheel to spin for an
extended period with the ESP ®
switched
off. Doing so may cause serious damage to
the drivetrain which is not covered by the
Mercedes-Benz Limited Warranty.
! Simultaneously depressing the
accelerator pedal and applying the brakes
reduces engine performance and causes
premature brake and drivetrain wear which
is not covered by the Mercedes-Benz
Limited Warranty. Hydroplaning
Depending
on the depth of the water layer on
the road, hydroplaning may occur, even at low
speeds and with new tires. In heavy rain or
when conditions indicate possible
hydroplaning: Driving instructions
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X
Make sure the automatic transmission is in
park position P (Y page 116).
X Engage the parking brake for the vehicle
(Y page 114).
X Start the engine (Y page 110).
X Vehicles with AIRMATIC:
Set the vehicle level to highway
(Y page 154) and set the ADS to AUTO or
COMF (Y page 153).
X Turn off the engine ( Y page 114).
X Close all doors and the tailgate.
X Attach the trailer.
X Plug in all electrical connectors.
i Vehicles with AIRMATIC:
When you are towing a trailer, the vehicle
level
always remains in the highway setting.
The following applies additionally when
towing a trailer:
R The vehicle is lowered to the highway
level when it reaches a speed of 5 mph
(8 km/h) if not set to highway level.
R The highspeed level is not available.
The restrictions that apply to towing also
apply when using accessories that are
connected to the trailer power socket, such
as a bicycle rack.
Towing a trailer There are many different laws, including
speed limit restrictions, having to do with
trailer

towing. Make sure your rig will be legal,
not only for where you reside, but also for
where you will be driving. A good source for
this information can be the police or local
authorities.
Note the following, when driving with a trailer:
R In order to gain skill and an understanding
of the vehicle’s behavior, you should practice turning, stopping and backing up
in an area which is free of traffic.
R Before you start driving check the
-trailer hitch
- break-away switch
- safety chains
- electrical connections
- lighting
- tires
R Adjust the mirrors

(Y page 94) to permit
unobstructed view beyond rear of trailer.
R If the trailer has electric brakes, start your
vehicle and trailer moving slowly, and then
apply only the trailer brake controller by
hand to make sure the brakes are working
properly.
R Always secure items in the trailer to
prevent load shifts while driving.
R When towing a trailer, check occasionally
to make sure the load is secure, and that
trailer lighting and brakes (if so equipped)
are functioning properly.
R Take into consideration that when towing a
trailer, the handling characteristics are
different and less stable from those when
operating the vehicle without a trailer.
It is important to avoid sudden maneuvers.
R The vehicle and trailer combination is
heavier, and therefore limited in
acceleration and climbing ability, and has a
larger braking distance.
It is more prone to reacting to cross wind
gusts, and requires more sensitive steering
input.
R If possible, do not brake abruptly, but
rather engage the brake slightly at first to
permit the trailer to activate its brake. Then
increase the braking force.
! If the trailer should begin to sway, reduce
the vehicle’s speed immediately. 258
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attack the paintwork as well as the vehicle
underbody and cause lasting damage.
Such damage is caused not only by extreme
and varying climatic conditions, but also by:
R
Air pollution
R Road salt
R Tar
R Gravel and stone chipping
To avoid paint damage, you should
immediately remove:
R Grease and oil
R Fuel
R Coolant
R Brake fluid
R Bird droppings
R Insects
R Tree resins etc.
Frequent
washing reduces and/or eliminates
the aggressiveness and potency of the above
adverse influences.
More frequent washings are necessary to
deal with unfavorable conditions:
R near the ocean
R in industrial areas (smoke, exhaust
emissions)
R during winter operation
You should check your vehicle from time to
time for stone chipping or other damage. Any
damage should be repaired as soon as
possible to prevent corrosion.
In doing so, do not neglect the underbody of
the vehicle. A prerequisite for a thorough
check is a washing of the underbody followed
by a thorough inspection. Damaged areas
need to be re-undercoated.
Your vehicle has been treated at the factory
with a wax-base rustproofing in the body
cavities which will last for the lifetime of the
vehicle. Post-production treatment is neither
necessary nor recommended by Mercedes-
Benz because of the possibility of incompatibility between materials used in the
production process and others applied later.
We have selected vehicle-care products and
compiled recommendations which are
specially matched to our vehicles and which
always
reflect the latest technology. You can
obtain Mercedes-Benz approved vehicle-care
products at an authorized Mercedes-Benz
Center.
Scratches, corrosive deposits, corrosion or
damage due to negligent or incorrect care
cannot always be removed or repaired with
the vehicle-care products recommended
here. In such cases it is best to seek aid at an
authorized Mercedes-Benz Center.
The following topics deal with the cleaning
and care of your vehicle and give important
“how-to” information as well as references to
Mercedes-Benz approved vehicle-care
products.
Power washer !
Follow the instructions provided by the
power washer manufacturer on
maintaining

a distance between the vehicle
and the nozzle of the power washer.
Never use a round nozzle to power-wash
tires. The intense jet of water can result in
damage to the tire.
Always replace a damaged tire.
Always keep the jet of water moving across
the surface. Do not aim directly at electrical
parts, electrical connectors, seals, or other
rubber parts.
i Vehicles with KEYLESS-GO:
If a door handle is hit by a strong jet of
water, and a SmartKey is within
approximately 3 ft (1 m) of the vehicle, it
could be inadvertently locked or unlocked.
Tar stains Quickly remove tar stains before they dry and
become more difficult to remove. A tar
remover is recommended. Vehicle care
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