Kevin Boden Tyre Sales

Tyre identification - The writing's on the wall

The writing and symbols on the sidewall of your tyre can tell you a great deal about the tyre itself, such as what weight it can carry and its maximum speed.
This helpful guide will show you what’s what, so that you can read the writing on the wall.
The writing on the sidewall of your tyre is like a specification sheet - it tells you everything you need to know about the tyre.
This information includes details of the tyre’s country of origin, size, speed rating, type approval, load capability, model number and much, much more.

Of course, some of this data is stuff only a tyre technician will find useful, but there are several details you will find handy too.

Let's use the Michelin MXV3A 175/65R14 82H shown as an example

MXV3A

- The Michelin pattern name.

175

- The nominal section width of the tyre in millimetres.

65

- The aspect ratio of the tyre, (the ratio between the section height and section width).

R

- Radial construction. Most car tyres sold in UK are radial except for certain special tyres such as space saver spares.

14

- The diameter of the rim shown in inches.

82

- The load capacity of the tyre shown as an index. which should be looked up on the load index table below. In this case the load capacity of the tyre at the correct inflation pressure is 475kg.

H

- The speed symbol, i.e. the maximum sustainable speed for the tyre at the load capacity given - in this case 130mph. View the Speed symbol Table below.

Steel Belted Radial

- as with the letter "R", this refers to the tyres construction. "Steel Belted" is a particular form of radial construction.

DOT

- the type approval mark of the American Department of Transport, showing that our tyres have passed their strict testing procedures.
When a tyre has passed both the American and European test programmes, you know you can have complete faith in it.

AB7C DEF267

- this is the tyre's production code marking, an internal code that allows us to determine exactly where and when a tyre was made.

E11 01234

- the ECE type approval mark and number, showing that the tyre have been tested and passed as high-quality by the European regulatory authorities.

Made in Great Britain

- the country where the tyre was made.

UTQG Markings

UTQG (Uniform Tyre Quality Grading) ratings measure a tyre's performance based on test results in three categories and allow you to better select your tyres.

The tests are carried out under strict conditions (on test tracks) and their results are informative
(See the example below: 280-A-A).

TREADWEAR

The treadware index represents how quickly a tyre becomes worn. This index is obtained by a test conducted on a test track over a distance of 6000 miles (9600 km), under controlled conditions. This index is between 60 and 620, with 100 as the reference standard. For example, a tyre with a treadware index of 50 will wear 2 times faster than a normal tyre whereas a tyre with a treadwear index of 280 will wear 2.8 times more slowly.

REMEMBER: The higher the treadwear index, the longer the life of the tyre.

TRACTION

The traction index represents a tyre's ability to stop on a wet road moving in a straight line. Traction grade does not include dry braking, cornering, and acceleration.
This index is indicated by the letters AA (highest index), A, B, C (lowest index). C is the lowest acceptable rating.

Grade AA: usually found on ultra high performance tyres: tyre performed very well on both the asphalt and cement surfaces
Grade A:    tyre performed well on both the asphalt and cement surfaces
Grade B:    tyre performed well on at least one of the surfaces
Grade C:    tyre performed poorly on one or both of the surfaces

REMEMBER: The higher the traction index, the shorter the braking distance.

TEMPERATURE

The temperature index represents a tyre's resistance to the generation of heat at high speeds and its ability to dissipate heat. This index is obtained by a laboratory test using a test wheel in a controlled environment with predetermined standards for tyre inflation and tyre load . Excessive heat can cause tyre degradation.

This index is indicated by the letters A (highest index), B, and C (lowest index). By law, C is the lowest acceptable rating.

A    Tyre withstood 30 minutes at speeds over 115 mph
B    Tyre withstood 30 minutes at 100 mph
C    Tyre withstood 30 minutes of speeds under 100 mph

REMEMBER: The temperature index "A" means that a tyre has good temperature resistance.

LOAD INDEX TABLE
Load Index	Kilograms	Load Index	Kilograms	Load Index	Kilograms
65	290	80	450	95	690
66	300	81	462	96	710
67	307	82	475	97	730
68	215	83	487	98	750
69	325	84	500	99	775
70	335	85	515	100	800
71	345	86	530	101	825
72	355	87	545	102	850
73	365	88	560	103	875
74	375	89	580	104	900
75	387	90	600	105	925
76	400	91	615	106	950
77	412	92	630	107	975
78	425	93	650	108	1000
79	437	94	670

SPEED SYMBOL TABLE
Speed Symbol	Approx MPH	Approx KPH
Q	99	160
R	106	170
S	112	180
T	118	190
H	130	210
V	150	240
ZR	150+	240+
W	168	270
Y	186	300

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