IndexSpeed rating
ZR...Y
1
up to 186 mph (300 km/h)
ZR...(..Y)
1
over 186 mph (300 km/h)
ZR
1
over 149 mph (240 km/h)
R
Specifying the speed rating as the "ZR" index
in tire code 4 is optional for tires up to
186 mph (300 km/h).
R
If your tire code 4 includes "ZR" and there
is no speed rating 7, find out what the max‐
imum speed is from the tire manufacturer.
R
If load-bearing index 6 and speed rating 7
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.
All-weather tires and winter tires
IndexSpeed rating
Q M+S
2
up to 100 mph (160 km/h)
T M+S
2
up to 118 mph (190 km/h)
H M+S
2
up to 130 mph (210 km/h)
V M+S
2
up to 149 mph (240 km/h)
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
traction on snow.
Load index 88:
R
No specification given: standard load (SL)
tire
R
"XL" or "Extra Load": extra load tire or rein‐
forced tire
R
"Light Load": light load tire
R
"C", "D", "E": a load range that depends on
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).
1
"ZR" stated in the tire code.
2
Or "M+S i" for winter tires
400
Wheels and tires
