spare wheel MERCEDES-BENZ B-CLASS 2012 User Guide

GAWR (Gross Axle Weight Rating)
The GAWR is
the maximum gross axle weight
rating. The actual load on an axle must never
exceed the gross axle weight rating. The
gross axle weight rating can be found on the
vehicle identification plate on the B-pillar on
the driver's side. Speed rating
The speed rating is part of the tire
identification. It specifies

the speed range for
which the tire is approved. GVW (Gross Vehicle Weight)
The gross vehicle weight includes the weight
of the vehicle including fuel, tools, the spare
wheel, accessories installed, occupants,
luggage and the drawbar noseweight, if
applicable. The gross

vehicle weight must not
exceed the gross vehicle weight rating GVWR
as specified on the vehicle identification plate
on the B-pillar on the driver's side. GVWR (Gross Vehicle Weight Rating)
The GVWR is

the maximum permissible gross
weight of a fully loaded vehicle (the weight of
the vehicle including all accessories,
occupants, fuel, luggage and the drawbar
noseweight, if applicable). The gross vehicle
weight rating is specified on the vehicle
identification plate on the B-pillar on the
driver's side. Maximum loaded vehicle weight
The maximum weight is the sum of:
R the curb weight of the vehicle
R the weight of the accessories
R the load limit
R the weight of the factory installed optional
equipment Kilopascal (kPa)
Metric unit for tire pressure. 6.9 kPa
corresponds to 1 psi. Another unit for tire
pressure is bar. 100 kilopascal (kPa) is the
equivalent of 1 bar . Load index
In addition to

the load-bearing index, the load
index may also be imprinted on the sidewall
of the tire. This specifies the load-bearing
capacity more precisely. Curb weight
The weight of a vehicle with standard
equipment including the maximum capacity
of fuel, oil

and coolant. It also includes the air-
conditioning system and optional equipment
if these are installed in the vehicle, but does
not include passengers or luggage. Maximum load rating
The maximum load rating in kilograms or
pounds is the maximum weight for which a
tire is approved. Maximum permissible tire pressure
Maximum permissible tire pressure for one
tire. Maximum load on one tire
Maximum load on one tire. This is calculated
by dividing the

maximum axle load of one axle
by two. PSI (pounds per square inch)
A standard unit of measure for tire pressure. Definition of terms for tires and loading
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Changing a wheel
Flat tire
You can find
information on what to do in the
event of a flat tire in the "Flat tire" section
(Y page 281). You will also find information
on driving with MOExtended tires in the event
of a flat tire.
Vehicle with emergency spare wheel: in
the event of a flat tire, the emergency spare
wheel is mounted as described under
"Mounting a wheel" ( Y page 319).Rotating the wheels
G
WARNING
Interchanging the front and rear wheels may
severely impair the driving characteristics if
the wheels or

tires have different dimensions.
The wheel brakes or suspension components
may also be damaged. There is a risk of
accident.
Rotate front and rear wheels only if the wheels
and tires are of the same dimensions.
Always pay attention to the instructions and
safety notes when changing a wheel
(Y page 319).
The wear patterns on the front and rear tires
differ, depending on the operating conditions.
Rotate the wheels before a clear wear pattern
has formed on the tires. Front tires typically
wear more on the shoulders and the rear tires
in the center.
If your vehicle's tire configuration allows, you
can rotate the wheels according to the
intervals in the tire manufacturer's warranty
book in your vehicle documents. If no
warranty book is available, the tires should be
interchanged every 3,000 to 6,000 miles
(5,000 to 10,000 km), or earlier if tire wear
requires. Do not change the direction of
wheel rotation.
Clean the contact surfaces of the wheel and
the brake disc thoroughly every time a wheel
is interchanged. Check the tire pressure and, if necessary, restart the tire pressure loss
warning system.
Direction of rotation
Tires with a specified direction of rotation
have additional benefits,

e.g. if there is a risk
of hydroplaning. You will only gain these
benefits if the correct direction of rotation is
maintained.
An arrow on the sidewall of the tire indicates
its correct direction of rotation. Storing wheels
Store wheels that

are not being used in a cool,
dry and preferably dark place. Protect the
tires from oil, grease, gasoline and diesel. Cleaning the wheels
G
WARNING
The water jet from a circular jet nozzle (dirt
blasters) can cause

invisible exterior damage
to the tires or chassis components.
Components damaged in this way may fail
unexpectedly. There is a risk of an accident.
Do not use power washers with circular jet
nozzles to clean the vehicle. Have damaged
tires or chassis components replaced
immediately. Mounting a wheel
Preparing the vehicle X
Stop the vehicle on solid, non-slippery and
level ground.
X Apply the electric parking brake manually
(Y page 150).
X Bring the front wheels into the straight-
ahead position.
X Move the DIRECT SELECT lever to position
P. Changing a wheel
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Tires
Summer tires Alloy wheels V1
BA
225/40 R18 92 W XL MOExtended
8, 9 7.5 J x 18 H2
Wheel offset: 2.05 in (52 mm) #
All-weather tires Alloy wheels V1
BA
225/45 R17 91 H M+SMOExtended
8, 9 7.5 J x 17 H2
Wheel offset: 2.07 in (52.5 mm
) #
Winter tires Alloy wheels V1
BA 205/50 R17 93 H XL M+S
i 6.5 J x 17 H2
Wheel offset: 1.93 in (49 mm) #
BA 205/50 R17 93 H XL
M+SiMOExtended
9 6.5 J x 17 H2
Wheel offset: 1.93 in (49 mm) #
Emergency spare wheel
Important safety notes
G
WARNING
The wheel or tire size as well as the tire type
of the spare
wheel or emergency spare wheel
and the wheel to be replaced may differ.
Mounting an emergency spare wheel may
severely impair the driving characteristics.
There is a risk of an accident.
To avoid hazardous situations:
R adapt your driving style accordingly and
drive carefully.
R never mount more than one spare wheel or
emergency spare wheel that differs in size.
R only use a spare wheel or emergency spare
wheel of a different size briefly.
R do not switch ESP ®
off.
R have a spare wheel or emergency spare
wheel of a different size replaced at the
nearest qualified specialist workshop. Observe that the wheel and tire dimensions
as well as the tire type must be correct.
When using an emergency spare wheel or
spare wheel of a different size, you must not
exceed the maximum speed of 50 mph
(80 km/h).
Snow chains must not be mounted on
emergency spare wheels. General notes
You should regularly check the pressure of
the emergency spare

wheel, particularly prior
to long trips, and correct the pressure as
necessary ( Y page 301). The value on the
wheel or as given in the "Technical data"
section ( Y page 323) is valid.
i When you are driving with the emergency
spare wheel mounted, the tire pressure
loss warning system cannot function
reliably. Only restart the tire pressure loss
8 Use of snow chains is not permitted. Observe the notes in the "Snow chains" section.
9 MOExtended tires (tires with run-flat characteristics) only in conjunction with activated tire pressure loss
warning. Emergency spare wheel
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warning system when the defective wheel
has been replaced with a new wheel.
An emergency spare wheel may also be
mounted against the direction of rotation.
Observe the time
restriction on use as well as
the speed limitation specified on the
emergency spare wheel.
Replace the tires after six years at the latest,
regardless of wear. This also applies to the
emergency spare wheel. Removing the emergency spare wheel
X
Open the tailgate.
X Loosen lashing straps ; on emergency
spare wheel bag :.
X Remove emergency spare wheel bag :
with the "Minispare" emergency spare
wheel.
For further information on changing and
mounting a wheel, see (
Y page 319). Technical data
"Minispare"
emergency spare
wheel
Tires Steel wheel
T 125/80 R17 99 M
Tire pressure: 420 kPa
(4.2 bar/61 psi) 3.5 B x 17 H2
ET 19.5326
Emergency spare wheel
Wheels and tires
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