Definition Of Terms For Tires And Loading - Mercedes-Benz E CLASS 2020 Operator's Manual

416 Wheels and tires
Index Speed rating
up to 186 mph (300 km/h)
ZR...Y 1
over 186 mph (300 km/h)
ZR...(..Y) 1
over 149 mph (240 km/h)
ZR 1
Specifying the speed rating as the "ZR" index
R
in tire code 4 is optional for tires up to
186 mph (300 km/h).
If your tire code 4 includes "ZR" and there
R
is no speed rating 7, find out what the max‐
imum speed is from the tire manufacturer.
If load-bearing index 6 and speed rating
R
are in brackets, the maximum speed rating of
your tire is above 186 mph (300 km/h). To
find out the maximum speed, ask the tire
manufacturer.
"ZR" stated in the tire code.
1
2 Or "M+S i" for winter tires
All-weather tires and winter tires
Index Speed rating
up to 100 mph (160 km/h)
2
Q M+S
up to 118 mph (190 km/h)
2
T M+S
up to 130 mph (210 km/h)
2
H M+S
2 up to 149 mph (240 km/h)
V M+S
Winter tires bear the i snowflake symbol
and fulfill the requirements of the Rubber Manu‐
facturers Association (RMA) and the Rubber
Association of Canada (RAC) regarding the tire
7
traction on snow.
Load index 8 8 :
No specification given: standard load (SL)
R
tire
"XL" or "Extra Load": extra load tire or rein‐
R
forced tire
"Light Load": light load tire
R
"C", "D", "E": a load range that depends on
R
the maximum load that the tire can carry at a
certain pressure

Definition of terms for tires and loading

Tire structure and characteristics: describes
the number of layers or the number of rubber-
coated belts in the tire contact surface and the
tire wall. These are made of steel, nylon, poly‐
ester and other materials.
Bar: metric unit for tire pressure.
14.5038 pounds per square inch (psi) and
100 kilopascal (kPa) is the equivalent of one bar.
DOT (Department of Transportation): DOT-
marked tires fulfill the requirements of the
US Department of Transportation.
Average weight of the vehicle occupants: the
number of vehicle occupants for which the vehi‐
cle is designed, multiplied by 150 lb (68 kg).