Preceding letter 11:
R
Without: passenger vehicle tires according to
European manufacturing standards.
R
"P": passenger vehicle tires according to US
manufacturing standards.
R
"LT": light truck tires according to US manu‐
facturing standards.
R
"T": compact emergency spare wheels with
high tire pressure that are only designed for
temporary use in an emergency.
Aspect ratio 3
3:
Ratio between tire height and tire width in per‐
cent (tire height divided by tire width).
Tire code 44 (tire type):
R
"R" radial tire
R
"D": bias ply tire
R
"B": bias belted tires
R
"ZR": radial tire with a maximum speed above
149 mph (240 km/h) (optional)
Rim diameter 55:
The diameter of the bead seat (not the diameter
of the rim flange). The rim diameter is specified
in inches (in).
Load-bearing index 6
6:
Numerical code that specifies the maximum
load-bearing capacity of a tire (e.g. "91" corre‐
sponds to 1356 lbs (615 kg)).
The load-bearing capacity of the tire must be at
least half the permissible axle load of your vehi‐
cle. Do not overload the tires by exceeding the
specified load limit.
See also:
R
Maximum permissible load on the Tire and
Loading Information placard (/ page 522)
R
Maximum tire load (/ page 528)
R
Load index
Speed rating 7
7:
Specifies the approved maximum speed of the
tire.
%
An electronic speed limiter prevents your
vehicle from exceeding a speed of 130 mph
(210 km/h).
Make sure that your tires have the required
speed rating. You can obtain information on the
required speed rating from an authorized
Mercedes-Benz Center.
Summer tires
IndexSpeed rating
Qup to 100 mph (160 km/h)
Rup to 106 mph (170 km/h)
Sup to 112 mph (180 km/h)
Tup to 118 mph (190 km/h)
Hup to 130 mph (210 km/h)
Vup to 149 mph (240 km/h)
Wup to 168 mph (270 km/h)
Yup to 186 mph (300 km/h)
530
Wheels and tires
