AUTORIDE

Tire Markings Explained: What does the code on the tire mean?

Tire
Udgivet af Martin Milo  Oversat ved hjælp af kunstig intelligens fra vores originale artikel (kilde: autoride.sk)

Tire markings might confuse many people, as they cannot find their way around various numbers and letters on the tire. The markings convey important information about tires, such as size, specs, and what kind of safety standards were met.

This extensive guide will show you how to decode the markings on a specific example, so you won't get lost when you see the symbols on the rubber of a tire.

Indholdsfortegnelse

What do the numbers on tires mean?

Tire marking

The main marking on the tire consists of a string of numbers (see the orange part of the string on the image) and might look like this: 205/65 R15. These numbers indicate the tire size, thus, are essential to ensure the tires fit your car. You can check your car's handbook for the appropriate size of tires. Let's split this string and decode each part:

  • 205 - Tire width in millimeters (from one sidewall to another)

  • 65 - Aspect ratio (tire height as a percentage of tire width, i.e., the height of this tire is 65% of the tire's width)

  • R - Construction of the tire - in this case, 'R' is abbreviated from "Radial" (you might also come across 'B' for Bias belt and 'D' for Diagonal)

  • 15 - Wheel/rim diameter in inches

Secondary tire markings explained

Besides the main marking, various other symbols on the tire might be confusing at the first glance. First, let's have a look at the secondary symbol from our example (see the image, white text on the tire) above that appeared after the main marking. The symbol is 91V, and can be divided into a number and a letter.

  • 91 - Load index, in this case, the maximum load is 615kg

  • V - Speed index/rating, in this case, the maximum speed is 240 kph (150 mph)

Load index

The load index represents a number and refers to a tire's maximum load in kilograms. The table below displays common load indexes and their respective loads. The load index for passenger tires usually spans from 75 to 105, though you can see indexes not included in this table if checking the tires for other types of vehicles.

LI

kg

LI

kg

LI

kg

50

190

75

387

100

800

51

195

76

400

101

825

52

200

77

412

102

850

53

206

78

425

103

875

54

212

79

437

104

900

55

218

80

450

105

925

56

224

81

462

106

950

57

230

82

475

107

975

58

238

83

487

108

1000

59

243

84

500

109

1030

60

250

85

515

110

1060

61

257

86

530

111

1090

62

265

87

545

112

1120

63

272

88

560

113

1150

64

280

89

580

114

1180

65

290

90

600

115

1215

66

300

91

615

116

1250

67

307

92

630

117

1285

68

315

93

650

118

1320

69

325

94

670

119

1360

70

335

95

690

120

1400

71

345

96

710

121

1450

72

355

97

730

122

1500

73

365

98

750

123

1550

74

375

99

775

124

1600

Speed index/rating

The speed rating is represented by a letter corresponding to the maximum speed a tire can sustain when carrying its recommended load.

SI

Maximum speed (mph)

Maximum speed (kph)

L

75

120

M

81

130

N

87

140

P

93

150

Q

99

160

R

106

170

S

112

180

T

118

190

U

124

200

H

131

210

V

149

240

VR

131

210

W

168

270

(W)

over 168

over 270

Y

186

300

(Y)

over 186

over 300

ZR

149

240

You might find it odd that the letter 'H' appears after 'U,' but it is not a mistake. If you check the complete table of speed indexes starting from the letter 'A,' you'd see that the letter 'H' is not present in the lower end.

Other tire markings

Tire marking

There are various other symbols besides the main and secondary tire markings. The tire usually displays the manufacturer's name, pattern, manufacturing date code, maximum load, temperature grade, and other symbols. It can also have tread wear indicators (TWI), country of manufacture, and E mark if the tire passes the EU's (European Union) safety standards.

Manufacturing date code (DOT)

The tire's manufacture date is marked, for example, as DOT F3OF OBDX 1422. The last four digits can be divided into two:

  • 14 - First two digits indicate the week of tire manufacture in the given year

  • 22 - Last two digits indicate the year the tire was manufactured

Common tire labels explained

BIAS BELTED

The cord plies are arranged at 30 to 40 degrees

RADIAL

The cord plies are arranged at 90 degrees to the direction of travel

TUBELESS

Tubeless tire (most of the tires for modern cars)

TUBETYPE

Tire that requires innertubes

RUN FLAT

The tire has reinforced sidewalls

M + S

Mud + Snow - Suitable for both muddy and snowy types of terrain

A/S

All season - Suitable for year-round driving

A/T

All-terrain - Universal tire for all types of terrain

R/T

Rugged terrain

M/T

Mud terrain - Suitable for muddy terrain

XL

Strengthened/reinforced tire

E mark table

Economic Commission for Europe (ECE) introduced the so-called E mark, which is mandatory on all tires sold in European.

Code

Country

Code

Country

E1

Germany

E21

Portugal

E2

France

E22

Russia

E3

Italy

E23

Greece

E4

Netherlands

E24

Ireland

E5

Sweden

E25

Croatia

E6

Belgium

E26

Slovenia

E7

Hungary

E27

Slovakia

E8

Czech Republic

E28

Belarus

E9

Spain

E29

Estonia

E10

Yugoslavia (former)

E31

Bosnia and Herzegovina

E11

United Kingdom

E32

Latvia

E12

Austria

E34

Bulgaria

E13

Luxembourg

E37

Turkey

E14

Switzerland

E40

Macedonia

E16

Norway

E43

Japan

E17

Finland

E45

Australia

E18

Denmark

E46

Ukraine

E19

Romania

E47

South Africa

E20

Poland

E48

New Zealand

Besides the country that produced and approved the tire, a standardized label indicates various properties of the tires, such as:

  • Grip in wet conditions

  • Rolling resistance

  • Road noise

These properties are graded from letters A-G, in which A is the best and G is the worst.

Conclusion

We hope this guide helped you understand various symbols and markings on the tire. If you think we miss something or want to share your thoughts, please let us know in the comments!