2010 MERCEDES-BENZ R320 trailer

Tire and Loading Information placard
i
Data shown on Tire and Loading
Information placard example are for
illustration purposes only. Load limit data
are specific to each vehicle and may vary
from data shown in the following
illustration. Refer to Tire and Loading
Information placard on vehicle for actual
data specific to your vehicle. The Tire and Loading Information placard
showing load limit information
: is located
on the driver’s door B-pillar ( Y page 236).
X Locate the statement “The combined
weight of occupants and cargo should
never exceed XXX kilograms or XXX lbs.”
on the Tire and Loading Information
placard.
The combined weight of all occupants,
cargo/luggage and trailer tongue load (if
applicable) should never exceed the weight
referenced in that statement.
Seating capacity i
Data shown on Tire and Loading
Information placard example are for
illustration purposes only. Seating capacity
data are specific to each vehicle and may
vary from data shown in the following
illustration. Refer to Tire and Loading
Information placard on vehicle for actual
data specific to your vehicle. The seating capacity gives you important
information on the number of occupants that
can be in the vehicle. Observe front and rear
seating capacity. The Tire and Loading
Information placard showing seating
capacity
: is located on the driver’s door
B-pillar ( Y page 236).
Steps for determining correct load limit The following steps have been developed as
required of all manufacturers under Title 49,
Code of U.S. Federal Regulations, Part 575
pursuant to the “National Traffic and Motor
Vehicle Safety Act of 1966”.
X
Step 1: Locate the statement “The
combined weight of occupants and cargo
should never exceed XXX kg or XXX lbs.”
on your vehicle’s Tire and Loading
Information placard.
X Step 2: Determine the combined weight of
the driver and passengers that will be riding
in your vehicle.
X Step 3: Subtract the combined weight of
the driver and passengers from
XXX kilograms or XXX lbs.
X Step 4: The resulting figure equals the
available amount of cargo and luggage load
capacity. For example, if the “XXX” amount
equals 1 400 lbs and there will be five
150 lbs passengers in your vehicle, the
amount of available cargo and luggage load
capacity is 650 lbs
(1 400 - 750 (5 x 150) = 650 lbs). Tires and wheels
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X
Step 5: Determine the combined weight of
luggage and cargo being loaded on the
vehicle. That weight may not safely exceed
the available cargo and luggage load
capacity calculated in step 4.
X Step 6 (if applicable): If your vehicle will
be towing a trailer, load from your trailer
will be transferred to your vehicle. Consult
this

manual to determine how this reduces
the available cargo and luggage load
capacity of your vehicle ( Y page 240).
The following table shows examples on how
to calculate total and cargo load capacities
with varying seating configurations and
number and size of occupants. The following
examples use a load limit of 1 500 lbs. This
is

for illustration purposes only. Make sure
you are using the actual load limit for your
vehicle stated on the vehicle’s Tire and
Loading Information placard ( Y page 237).238
Tires and wheels
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Example 1 Example 2 Example 3
Step 1 Combined weight limit
of
occupants and cargo
from Tire and Loading
Information placard 1 500 lbs 1 500 lbs 1 500 lbs
Example 1 Example 2 Example 3
Step 2 Number of occupants
(driver

and passengers) 5 3 1
Seating configuration
front: 2
rear: 3 front: 1
rear: 2 front: 1
Occupants weight
Occupant 1:
150 lbs
Occupant 2:
180 lbs
Occupant 3:
160 lbs
Occupant 4:
140 lbs
Occupant 5:
120 lbs Occupant 1:
200 lbs
Occupant 2:
190 lbs
Occupant 3:
150 lbs Occupant 1:
150 lbs
Combined weight of all
occupants
750 lbs 540 lbs 150 lbs
Example 1 Example 2 Example 3
Step 3 Available cargo/
luggage and trailer
tongue weight (total
load

limit from Tire and
Loading Information
placard minus
combined weight of all
occupants) 1 500 lbs -
750 lbs =
750 lbs 1 500 lbs -
540 lbs =
960 lbs 1 500 lbs -
150 lbs =
1 350 lbs
The higher the weight of all occupants, the
less cargo and luggage load capacity is
available.
For more information, see “Trailer tongue
load”

(Y page 240). Certification label Even after careful determination of the
combined

weight of all occupants, cargo and
the trailer tongue load (if applicable)
(Y page 240) as to not exceed the
permissible load limit, you must make sure
your vehicle never exceeds the Gross Vehicle Tires and wheels
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Weight Rating (GVWR) and the Gross Axle
Weight Rating (GAWR) for either the front or
rear axle. You can obtain the GVWR and
GAWR from the certification label. The
certification label can be found on the driver’s
door B-pillar, see the “Technical data” section
(Y page 344).
Gross Vehicle Weight Rating (GVWR): The
total weight of the vehicle, all occupants, all
cargo, and the trailer tongue load (if
applicable) must never exceed the GVWR.
Gross Axle Weight Rating (GAWR): The total
allowable weight that can be carried by a
single axle (front or rear).
To assure that your vehicle does not exceed
the maximum permissible weight limits
(GVWR and GAWR for front and rear axle),
have the loaded vehicle (including driver,
passengers and all cargo and, if applicable,
trailer fully loaded) weighed on a suitable
commercial scale.
Trailer tongue load
The tongue load of any trailer is an important
weight to measure because it affects the load
you can carry in your vehicle. If a trailer is
towed, the tongue load must be added to the
weight of all occupants riding and any cargo
you are carrying in the vehicle. The tongue
load typically is between 10% and 15% of the
trailer weight and everything loaded in it.
Maximum tire load
G
Warning!
Do not overload the tires by exceeding the
specified load limit as indicated on the Tire
and Loading Information placard on the
driver’s door B-pillar. Overloading the tires
can overheat them, possibly causing a
blowout. Overloading the tires can also result
in handling or steering problems, or brake
failure. i
For illustration purposes only. Actual data
on tires are specific to each vehicle and
may vary from data shown in above
illustration.
The maximum tire load rating : is the
maximum weight the tires are designed to
support.
For more information on tire load rating, see
(Y page 245).
For information on calculating total and cargo
load capacities, see ( Y page 237). Direction of rotation
Unidirectional tires offer added advantages,
such as better hydroplaning performance. To
benefit, however, you must make sure the
tires rotate in the direction specified.
An arrow on the sidewall indicates the
intended direction of rotation of the tire.
Spare wheels may be mounted against the
direction of rotation (spinning) even with a
unidirectional tire for temporary use only until
the regular drive wheel has been repaired or
replaced. Always observe and follow
applicable temporary use restrictions and
speed limitations indicated on the spare
wheel. MOExtended 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. 240
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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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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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X
Reduce vehicle speed.
X Avoid track grooves in the road.
X Apply brakes cautiously. Standing water
! Do not drive through flooded areas.
Before
driving through water, determine its
depth.
If you must drive through standing water,
drive slowly to prevent water from entering
the passenger compartment or the engine
compartment. Water in these areas could
cause damage to electrical components or
wiring of the engine or transmission, or
could result in water being ingested by the
engine through the air intake causing
severe internal engine damage. Any such
damage is not covered by the Mercedes-
Benz Limited Warranty.
Prevent water from entering the passenger
compartment or the engine compartment. If
you must drive through standing water, keep
in mind that
R the maximum depth of the water may not
exceed 10 in (25 cm)
R you must drive slowly
i Vehicles with AIRMATIC:
If you have selected the raised level
(Y page 155) before driving through
standing water, the maximum water depth
is 12 in (30 cm). Trailer towing
G
Warning!
Failure to use proper equipment and driving
technique can result in a loss of vehicle
control when towing a trailer.
Improper towing or failure to follow the
instructions in this manual can result in
vehicle damage and/or serious personal injury. Follow the guidelines below carefully
to assure safe trailer operation.
Contact

an authorized Mercedes-Benz Center
should you require an explanation of
information contained in this manual.
Trailer hitch R
Only
install a trailer hitch receiver approved
for your vehicle.
For information on availability and
installation, contact an authorized
Mercedes-Benz Center.
R The bumpers on your vehicle are not
designed for use with clamp-type hitches.
Do not attach rental hitches or other
bumper-type hitches to them.
R To reduce the possibility of damage,
remove the hitch ball adapter from the
receiver when not in use.
Electrical connections The vehicle is prewired to accept the seven-
wire harness included in the Mercedes-Benz
approved trailer hitch receiver kit.
i
A four-pole conversion plug is available
from your authorized Mercedes-Benz
Center as a spare part.
For further information, contact an
authorized Mercedes-Benz Center.
Vehicle

and trailer weights and ratings The Gross Trailer Weight (GTW) is the weight
of the trailer plus the weight of all cargo,
equipment, luggage, etc. loaded on the
trailer. The maximum permissible GTW to be
towed: 3
500 lb (1 588 kg).
Trailer Tongue Weight Rating (TWR) is the
maximum permissible weight on the trailer
tongue: 350 lb (158 kg) limit for Mercedes-
Benz approved hitch receiver. 256
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Loading a trailer
R
When
loading a trailer, you should observe
that neither the permissible GTW, nor the
Gross Vehicle Weight Rating (GVWR) are
exceeded. The GVWR is indicated on the
certification label located on the driver’s
door B-pillar ( Y page 236).
Maximum permissible values are listed on
the safety compliance certification labels
for the vehicle and for the trailer to be
towed.
The lowest value listed must be selected
when determining how the vehicle and
trailer are loaded.
R The tongue weight at the hitch ball must be
added to the rear axle weight to prevent
exceeding the rear Gross Axle Weight
Rating (GAWR). The GAWR is indicated on
the certification label located on the
driver’s door B-pillar ( Y page 236).
i Mercedes-Benz recommends loading the
trailer in such a manner that it has a tongue
weight between 8 % and 10 % of the GTW.
i The weight of other accessories,
passengers and cargo will reduce the
maximum trailer weight and tongue weight
your vehicle can tow.
Checking weights of vehicle and trailer
R To assure that the towing vehicle and trailer
are in compliance with the maximum
permissible weight limits, have the loaded
rig (towing vehicle including driver,
passengers and cargo, trailer fully loaded)
weighed on a commercial scale.
R Check the vehicle’s front and rear gross
axle weight, the Gross Trailer Weight (GTW)
and tongue weight.
The values as measured must not exceed
the weight limits listed under “Vehicle and
trailer weights and ratings” ( Y page 256).Coupling a trailer G
Warning!
Vehicles with AIRMATIC: While you are
coupling or decoupling a trailer, make sure
nobody locks or unlocks the vehicle and/or
opens or closes doors or the tailgate.
The vehicle’s level could change and you
could endanger yourself and/or others as a
result.
Make sure that you do not operate the ADS
switch or the vehicle level control system
when coupling/decoupling the trailer.
Observe maximum permitted trailer
dimensions (width and length).
Most states and all Canadian provinces
require
R safety chains between the towing vehicle
and the trailer
The chains should be criss-crossed under
the trailer tongue. They must be attached
to the hitch receiver, and not to the
vehicle’s bumper or axle.
Make sure to leave enough slack in the
chains to permit turning corners.
R a separate brake system at various trailer
weights
R a break-away switch on trailers with a
separate brake system.
Check

with your local state laws for specific
requirements.
The switch activates the trailer brakes in
the possible event that the trailer might
separate from the tow vehicle.
! Do not connect a trailer brake system (if
trailer is so equipped) directly to the
vehicle’s hydraulic brake system, as your
vehicle is equipped with antilock brakes. If
you do, neither the vehicle’s brakes nor the
trailer’s brakes will function properly.
i The provided vehicle electrical wiring
harness for trailer towing has a brake signal
wire for hook-up to a brake controller. Driving instructions
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