tires MERCEDES-BENZ B-CLASS 2012 Owner's Guide
[x] Cancel search | Manufacturer: MERCEDES-BENZ, Model Year: 2012, Model line: B-CLASS, Model: MERCEDES-BENZ B-CLASS 2012Pages: 340, PDF Size: 3.09 MB
Page 306 of 340
Observe the recommended tire pressures for
cold tires:
R
on the Tire
and Loading Information placard
on the B-pillar on the driver's side
R in the tire pressure table on the inside of
the fuel filler flap Underinflated or overinflated tires
Underinflation G
WARNING
Tires with pressure that is too low can
overheat and burst as a consequence. In
addition, they also
suffer from excessive and/
or irregular wear, which can severely impair
the braking properties and the driving
characteristics. There is a risk of an accident.
Avoid tire pressures that are too low in all the
tires, including the spare wheel.
Underinflated tires may:
R wear quickly and unevenly
R have an adverse effect on fuel consumption
R overheat, leading to tire defects
R have an adverse effect on handling
characteristics
Overinflation G
WARNING
Tires with excessively high pressure can burst
because they are damaged more easily by
road debris, potholes etc. In addition, they
also suffer from irregular wear, which can
severely impair the
braking properties and the
driving characteristics. There is a risk of an
accident.
Avoid tire pressures that are too high in all the
tires, including the spare wheel.
Overinflated tires may:
R have an adverse effect on handling
characteristics
R wear quickly and unevenly R
be more susceptible to damage
R have an adverse effect on ride comfort
R increase the braking distance
Maximum tire pressures Never exceed the maximum permissible tire
inflation pressure. Always observe the
recommended tire pressure for your vehicle
when adjusting the tire pressure
(Y page 301).
:
Example: maximum permissible tire
pressure
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 "Tire pressure information"
section (
Y page 301).
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
R on the tire pressure label on the fuel filler
flap
R in the "Tire pressure information" section304
Tire pressure
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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 on the
B-pillar on the
driver's side of your vehicle.
X If necessary, increase the tire pressure to
the recommended value ( Y page 301).
X If the tire pressure is too high, release air
by pressing down
the metal pin in the valve
using 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
Important safety 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.
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 301).
The tire pressure loss warning system does
not replace the need to regularly check your
vehicle's tire pressures, since 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 loss warning system 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 to your vehicle's
tires.
R road conditions are wintry.
R you are driving on sand or gravel.
R you adopt a very sporty driving style
(cornering at high speeds or driving with
high rates of acceleration).
R you are driving with a heavy load (in the
vehicle or on the roof).
Restarting the tire pressure loss
warning system Restart the tire pressure loss warning system
if you have:
R
changed the tire pressure
R changed the wheels or tires
R mounted new wheels or tires
X Before restarting, make sure that the tire
pressures are set properly on all four tires
for the respective operating conditions.
The recommended tire pressures can be
found in the table on the fuel filler flap.
The tire pressure loss warning system can
only give reliable warnings if you have set
the correct tire
pressure. If an incorrect tire
pressure is set, these incorrect values will
be monitored.
X Observe the notes on tire pressure
(Y page 301).
X Make sure that the SmartKey is in
position 2 (Y page 135)
in the ignition lock. Tire pressure
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X
Press = or ; on the steering wheel
to select the Service menu.
X Press the 9 or : button to select
Tire Pressure.
X Press the a button.
The Run Flat Indicator Active
Press 'OK' to Restart message
appears in the multifunction display.
If you wish to confirm the restart:
X Press the a button.
The Tire Pressure Now OK? message
appears in the multifunction display.
X Press the 9 or : button to select
Yes.
X Press the a button.
The Run Flat Indicator Restarted
message appears in the multifunction
display.
After a teach-in period, the tire pressure
loss warning system will monitor the set
tire pressures of all four tires.
or
If you wish to cancel the restart:
X Press the % button.
or
X If the Tire Pressure Now OK? message
appears, use the 9 or : button to
select Cancel.
X Press the a button.
The tire pressure values stored at the last
restart will continue to be monitored. Loading the vehicle
Instruction labels for tires and loads
G
WARNING
Overloaded tires can overheat, causing a
blowout. Overloaded tires
can also impair the
steering and driving characteristics and lead
to brake failure. There is a risk of accident.
Observe the load rating of the tires. The load
rating must be at least half of the GAWR of your vehicle. Never overload the tires by
exceeding the maximum load.
:
B-pillar, driver's side
Two instruction labels on your vehicle show
the maximum possible load.
(1) The Tire and Loading Information placard is on the
B-pillar on the driver's side. The
Tire and Loading Information placard
shows the maximum permissible number
of occupants and the maximum
permissible vehicle load. It also contains
details of the tire sizes and
corresponding pressures for tires
mounted at the factory.
(2) The vehicle identification plate is on the B-pillar on the driver's side. The vehicle
identification plate informs you of the
gross vehicle weight
rating. It is made up
of the vehicle weight, all vehicle
occupants, the fuel and the cargo. You
can also find information about the
maximum gross axle weight rating on the
front and rear axle.
The maximum gross axle weight rating is
the maximum weight that can be carried
by one axle (front or rear axle). Never
exceed the maximum load or the
maximum gross axle weight rating for the
front or rear axle. 306
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Maximum permissible gross vehicle
weight rating
X
Specification for maximum gross vehicle
weight : is listed in the Tire and Loading
Information placard: "The
combined weight
of occupants and cargo should never
exceed XXX kilograms or XXX lbs."
The gross weight of all vehicle occupants,
load, luggage and trailer load/noseweight (if
applicable) must not exceed the specified
value.
i The specifications shown on the Tire and
Loading Information placard in the
illustration are examples. The maximum
permissible load is vehicle-specific and
may deviate from
the data shown here. The
maximum permissible load that applies for
your vehicle can be found on your vehicle's
Tire and Loading Information placard. Number of seats
Maximum number of seats
: indicates the
maximum number of occupants allowed to travel in the vehicle. This information can be
found on the Tire and Loading Information
placard.
i
The specifications shown on the Tire and
Loading Information placard in the
illustration are examples. The number of
seats is
vehicle-specific
and can differ from
the details shown. The number of seats in
your vehicle can be found on the Tire and
Loading Information placard. Determining the correct load limit
Step-by-step instructions 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 1400 lbs and there are five
occupants in the vehicle each with a weight
of 150 lbs, the amount of available cargo
and luggage load capacity is 650 lbs (1400
Ò 750 (5 x 150) = 650 lbs).
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 Loading the vehicle
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will be transferred to your vehicle. Refer to
this Operator's Manual to determine how
this reduces the available cargo and
luggage load capacity of your vehicle
(Y page 310).308
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Example: steps 1 to 3
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 maximum load of 1500 lbs (680 kg). This is for illustration purposes only. Make sure you
are using the actual load limit for your vehicle stated on your vehicle's Tire and Loading
Information placard (Y page 307).
The greater the combined weight of the occupants, the lower the maximum luggage load. Example 1 Example 2 Example 3
Step 1 Combined maximum
weight of occupants
and cargo
(data
from
the Tire and Loading
Information placard) 1500 lbs
(680 kg) 1500 lbs
(680 kg) 1500 lbs
(680 kg)
Example 1 Example 2 Example 3
Step 2 Number of people in
the vehicle (driver
and occupants)
5 3 1
Distribution of the
occupants
Front: 2
Rear: 3 Front: 1
Rear: 2 Front: 1
Weight of the
occupants
Occupant 1:
150 lbs (68 kg)
Occupant 2:
180 lbs (82 kg)
Occupant 3:
160 lbs (73 kg)
Occupant 4:
140 lbs (63 kg)
Occupant 5:
120 lbs (54 kg) Occupant 1:
200 lbs (91 kg)
Occupant 2:
190 lbs (86 kg)
Occupant 3:
150 lbs (68 kg) Occupant 1:
150 lbs (68 kg)
Gross weight of all
occupants
750 lbs (340 kg) 540 lbs (245 kg) 150 lbs (68 kg)Loading the vehicle
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Example 1 Example 2 Example 3
Step 3 Permissible load and
trailer load/
noseweight
(maximum
permissible load
rating from the Tire
and Loading
Information placard
minus the gross
weight of all
occupants)
1500 lbs
(680 kg)
Ò750 lbs
(340 kg) =
750 lbs
(340
kg) 1500 lbs
(680 kg)
Ò540 lbs
(245 kg) =
960 lbs
(435
kg) 1500 lbs
(680 kg)
Ò150 lbs (68 kg)
= 1350 lbs
(612 kg)
Vehicle identification plate
Even if you have calculated the total cargo
carefully, you should still make sure that the
gross vehicle weight
rating and the gross axle
weight rating are not exceeded. Details can
be found on the vehicle identification plate on
the B-pillar on the driver's side of the vehicle
(Y page 306).
Permissible gross vehicle weight: the
gross weight of the vehicle, all passengers,
load and trailer load/noseweight (if
applicable) must not exceed the permissible
gross vehicle weight.
Gross axle weight rating: the maximum
permissible weight that can be carried by one
axle (front or rear axle).
To ensure that your vehicle does not exceed
the maximum permissible values (gross
vehicle weight and maximum gross axle
weight rating), have your loaded vehicle
(including driver, occupants, cargo, and full
trailer load if applicable) weighed on a
suitable vehicle weighbridge. Trailer load/noseweight
The trailer load/noseweight
affects the gross
weight of the vehicle. If a trailer is attached,
the trailer load/noseweight is included in the
load along with occupants and luggage. The
trailer load/noseweight is usually between 10% and 15% of the gross weight of the trailer
and its load.
Maximum load rating
Do not overload the tires by exceeding the
specified load limit. The maximum
permissible load can be found on the
vehicle's Tire and Loading Information
placard on the B-pillar on the driver's side
( Y
page 306). Maximum tire load
: is the maximum
permissible weight for which the tire is
approved.
i The actual values for tires are vehicle-
specific and may
deviate from the values in
the illustration. 310
Maximum load rating
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Uniform Tire Quality Grading
Standards
Overview of Tire Quality Grading
Standards
Uniform Tire Quality Grading Standards are
U.S. government specifications. Their
purpose is to provide drivers with uniform
reliable information
on
tire performance data.
Tire manufacturers have to grade tires using
three performance factors: tread wear :,
tire traction ;, and heat resistance =.
These regulations do not apply to Canada.
Nevertheless, all tires sold in North America
are provided with the corresponding quality
grading markings on the sidewall of the tire.
All passenger car tires must conform to the
statutory safety requirements in addition to
these grades.
Where applicable, the tire grading
information can be found on the tire sidewall
between the tread shoulder and maximum
tire width.
i The actual values for tires are vehicle-
specific and may deviate from the values in
the illustration.
For example: Treadwear Traction Temperature
200 AA A Treadwear
The treadwear grade is a comparative rating
based on the
wear rate of the tire when tested
under controlled conditions on a specified
U.S. government course. For example, a tire
graded 150 would wear one and one-half
times as well on the government course as a
tire graded 100.
The relative performance of tires depends
upon the actual conditions of their use,
however, and may depart significantly from
the norm, due to variations in driving habits,
service practices and differences in road
characteristics and climate conditions. Traction
G
WARNING
The traction grade assigned to this tire is
based on straight-ahead braking traction
tests, and does not include acceleration,
cornering, hydroplaning, or peak traction
characteristics.
The traction grades, from highest to lowest,
are AA, A, B, and C. Those grades represent
the tire's ability to stop on a wet surface as
measured under controlled conditions on
specified government test
surfaces of asphalt
and concrete. A tire marked C may have poor
traction performance.
The safe speed on a wet, snow covered or icy
road is always lower than on dry road
surfaces.
You should pay special attention to road
conditions when temperatures are around
the freezing point.
Mercedes-Benz recommends a minimum
tread depth of ã in (4 mm) for all four winter
tires ( Y page 300) to maintain normal driving
characteristics in winter. Winter tires can
reduce the braking distance on snow-covered
surfaces in comparison with summer tires.
Stopping distance, however, is still
considerably greater than when the road is Uniform Tire Quality Grading Standards
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not covered with ice or snow. Take
appropriate care when driving.
!
Avoid wheelspin. This
can lead to damage
to the drive train. Temperature
G
WARNING
The temperature grade for this tire is
established for a tire that is properly inflated
and not overloaded. Excessive speed,
underinflation, or excessive loading, either
separately or in combination, can cause
excessive heat build-up and possible tire
failure.
The temperature grades are A (the highest),
B, and C. These represent the tire's
resistance to the generation of heat and its
ability to dissipate heat when tested under
controlled conditions on a specified indoor
laboratory test wheel. Sustained high
temperature can cause
the material of the tire
to degenerate and reduce tire life, and
excessive temperature can lead to sudden
tire failure. The grade C corresponds to a level
of performance which all passenger car tires
must meet under the Federal Motor Vehicle
Safety Standard No. 109. Grades B and A
represent higher levels of performance on the
laboratory test wheel than the minimum
required by law. Tire labeling
Overview of tire labeling
The following markings are on the tire in addition
to the tire name (sales designation) and the
manufacturer's name:
:
Uniform tire Quality Grading Standard
(Y page 316)
; DOT, Tire Identification Number
(Y page 315)
= Maximum tire load ( Y page 310)
? Maximum tire pressure (Y page 304)
A Manufacturer
B Tire material ( Y page 316)
C Tire size designation, load-bearing
capacity and speed index (
Y page 313)
D Load index ( Y
page 315)
E Tire name
i Tire data is vehicle-specific and may
deviate from the data in the example. 312
Tire labeling
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Tire size designation, load-bearing
capacity and speed rating
:
Tire width
; Nominal aspect ratio in %
= Tire code
? Rim diameter
A Load bearing index
B Speed rating
i Tire data is vehicle-specific and may
deviate from the data in the example.
General: depending on the manufacturer's
standards, the size imprinted in the tire wall
may not contain any letters or may contain
one letter
that
precedes the size description.
If there is no letter preceding the size
description (as shown above): these are
passenger vehicle tires according to
European manufacturing standards.
If "P" precedes the size description: these are
passenger vehicle tires according to U.S.
manufacturing standards.
If "LT" precedes the size description: these
are light truck tires according to U.S.
manufacturing standards.
If "T" precedes the size description: these are
compact emergency spare wheels at high tire
pressure, to be used only temporarily in an
emergency.
Tire width: tire width : shows the nominal
tire width in millimeters.
Nominal aspect ratio: aspect ratio ; is the
size ratio between the tire height and the tire
width and is shown in percent. The aspect ratio is calculated by dividing the tire width by
the tire height.
Tire code:
tire code =
specifies the tire type.
"R" represents radial tires; "D" represents
diagonal tires; "B" represents diagonal radial
tires.
Optionally, tires with a maximum speed of
over 149mph (240km/h) may have "ZR" in
the size description, depending on the
manufacturer (e.g. 245/40 ZR 18).
Rim diameter: rim diameter ? is the
diameter of the bead seat, not the diameter
of the rim flange. The rim diameter is
specified in inches (in).
Load bearing index: load bearing index A
is a numerical code which specifies the
maximum load-bearing capacity of a tire.
Do not overload the tires by exceeding the
specified load limit. The maximum
permissible load can be found on the
vehicle's Tire and Loading Information
placard on the B-pillar on the driver's side
(Y page 306).
Example:
A load-bearing index of 91 indicates a
maximum load of 1,356lb (615kg) that can be
carried by the tires. For further information on
the maximum tire load in kilograms and
pounds, see (Y page 310).
For further information on the load-bearing
index, see Load index ( Y page 315).
Speed rating: speed rating B specifies the
approved maximum speed of the tire. G
WARNING
Exceeding the stated tire load-bearing
capacity and the approved maximum speed
could lead to
tire damage or the tire bursting.
There is a risk of accident.
Therefore, only use tire types and sizes
approved for your vehicle model. Observe the
tire load rating and speed rating required for
your vehicle.
Regardless of the speed rating, always
observe the speed limits. Drive carefully and Tire labeling
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