Mercedes-Benz G 550 2015 Operator's Manual page 247

pressure, to be used only temporarily in an
emergency.
Tire width: tire width : shows the nominal
tire width in millimeters.
Height-width ratio: height-width ratio ; is
the ratio between tire height and tire width.
The aspect ratio is calculated by dividing the
tire width by the tire height. The resulting
quotient is given as a percentage.
Tire code: tire code = shows the tire type.
"R" represents radial tires; "D" represents
diagonal tires; "B" represents diagonal radial
tires.
Optionally, tires with a maximum speed of
over 149 mph (240 km/h) may have "ZR" in
the size description, depending on the man-
ufacturer (e.g. 245/40 ZR 18).
Rim diameter: rim diameter ? is the diam-
eter of the bead seat, not the diameter of the
rim flange. The rim diameter is specified in
inches (in).
The load-bearing index: load-bearing index
A (also load index), is a code that contains
the maximum load-bearing capacity of a tire.
Do not overload the tires by exceeding the
specified load limit. The maximum permissi-
ble load can be found on the vehicle's Tire and
Loading Information placard on the B-pillar on
the driver's side ( page 238).
Y
Example:
Load-bearing index 91 indicates a maximum
load of 1,356 lb (615 kg) that the tires can
bear. For further information on the maximum
tire load in kilograms and pounds, see
( page 246).
Y
For further information on the load bearing
index, see "Load index" (
Speed rating: speed rating B specifies the
approved maximum speed of the tire.
Tire data is vehicle-specific and may devi-
i
ate from the data in the example.
Regardless of the speed rating, always
observe the speed limits. Drive carefully and
adapt your driving style to the traffic condi-
tions.
i
Summer tires
Index
Q
R
S
T
H
V
W
Y
ZR...Y
ZR...(..Y)
ZR
R
R
page 246).
Y
Tire labeling
Since 2009, tires in Europe which corre-
spond to the noise limitations of Directive
ECE-R 117 show an >>S<< (Sound) mark.
This identification follows the type approval
number and has no connection with the
speed rating.
Speed rating
up to 100 mph (160 km/h)
up to 106 mph (170 km/h)
up to 112 mph (180 km/h)
up to 118 mph (190 km/h)
up to 130 mph (210 km/h)
up to 149 mph (240 km/h)
up to 168 mph (270 km/h)
up to 186 mph (300 km/h)
up to 186 mph (300 km/h)
over 186 mph (300 km/h)
over 149 mph (240 km/h)
Optionally, tires with a maximum speed of
over 149 mph (240 km/h) may have "ZR" in
the size description, depending on the
manufacturer (e.g. 245/40 ZR18).
The service specification is made up of
load-bearing index A and speed rating B.
If the size description of your tire includes
"ZR" and there are no service specifica-
tions, ask the tire manufacturer in order to
find out the maximum speed.
If a service specification is available, the
maximum speed is limited according to the
speed rating in the service specification.
Example: 245/40 ZR18 97 Y. In this exam-
ple, "97 Y" is the service specification. The
letter "Y" represents the speed rating and
245
Z