Tyre Symbols & Ratings – Explained

[Darcon666]

With all the talk about tyres I thought I might post this up... as there is nothing on the forum with this info all in one place...hope it helps.

NOTE:- PLEASE take note of the recommended tyre ratings by the Vehicles Manufacturers as to acceptable tyre ratings/load/size... we should not go below these recommended minimums unless advised by a tyre specialist/professional.

How do I tell the age of a tyre?

All tyres are produced with a serial Tyre Identification Number (or serial TIN) that shows the date of manufacture of a tyre. The last three digits (for tyres made pre 2000) or four digits (for post 2000 tyres) of the serial TIN indicate the week and year that the tyre was made.
The date the tyre was manufacture is usually stamped on the sidewall, usually within an oval shaped indent on one side of the tyre ONLY.

Example 1). “2610” = 26th Week of 2010.
Example 2). “378” = 37th Week of 1998.

Also a tyre made in the 1990's can be distinguished from a tyre made in the 1980's due to a triangular indentation after the last number which is not present on 1980's tyres.

You should replace your tyres, regardless of amount of tread still left on them and/or condition they appear to be in... if they are over 5-6 years old from the date of manufacture. This is what industry specialist and manufacturers recommend as “Rubber” loses stability over time.

Tread Wear Grade

The treadwear grade is a comparative rating based on the wear of a tyre when tested carefully under controlled conditions. For example the useful tread on a tyre graded 400 should last twice as long as a tyre graded 200. However, another tyre manufacturer may grade a comparable design 300, so a grade of 150 would last just half as long under their grading scheme. The lesson learned is to not use one manufacturer's grade versus the other, but instead to compare tyre grades within a given brand. Actual treadwear performance can vary tremendously according to the tyre's real-world use. Variations in driving habits, service practices (most importantly air pressure maintenance), road conditions and climate affect tyre life.

Traction Grades

Traction grades represent the tyre's ability to stop on wet pavement as measured under controlled conditions on asphalt and concrete test surfaces. As of 1997, the traction grades from highest to lowest are "AA","A","B" and "C". A tyre graded "AA" may have relatively better traction performance than a tyre graded lower, based on straight-ahead braking tests. The grades do not take into consideration the cornering or turning performance of a tyre.

Temperature Grades

Temperature grades represent a tyre's resistance to heat and its ability to dissipate heat when tested under controlled laboratory test conditions. The grades from highest to lowest are "A","B" and "C". The grade "C" corresponds to the minimum performance required by federal safety standard. Therefore, the "A" tyre is the coolest running, and even though the "C" tyre runs hotter it does not mean it is unsafe. The temperature grade is established for a tyre that is properly inflated and not overloaded.

"N" For cars with a speed capability not exceeding 140 Km/h (88 Mph)
"P" For cars with a speed capability not exceeding 150 Km/h (94 Mph)
"Q" For cars with a speed capability not exceeding 160 Km/h (100 Mph)
"R" For cars with a speed capability not exceeding 170 Km/h (106 Mph)
"S" For cars with a speed capability not exceeding 180 Km/h (113 Mph)
"T" For cars with a speed capability not exceeding 190 Km/h (119 Mph)
"U" For cars with a speed capability not exceeding 200 Km/h (125 Mph)
"H" For cars with a speed capability not exceeding 210 Km/h (130 Mph)
"V" For cars with a speed capability not exceeding 240 Km/h (e.g. 225.55 R 15 91V)
"W" For cars having speed capability not exceeding 270 Km/h (e.g. 225.60 R 15 96W)
"Y" For cars having speed capability not exceeding 300 Km/h (e.g. 275.40 R 18 94Y)
"VR" For cars having speed capability over 210 Km/h (e.g. 195.50 VR 15)
"ZR" For cars with a speed capability over 240 Km/h (e.g. 205.40 ZR 17)
"ZR+" "W" Tyres marked with both designations for cars with speed capability over 240 Km/h but not exceeding 270 Km/h
"ZR+" "Y" Tyres marked with both designations for cars with speed capability over 240 Km/h but not exceeding 300 Km/h


Standard Load Table (extract from E.T.R.T.O Standards Manual)

Code / Pounds / Kilograms(Not all apply to our vehicles...)
60 / 551 / 250
61 / 567 / 257
62 / 584 / 265
63 / 600 / 272
64 / 617 / 280
65 / 640 / 290
66 / 661 / 300
67 / 677 / 307
68 / 695 / 315
69 / 717 / 325
70 / 738 / 335
71 / 761 / 345
72 / 783 / 355
73 / 805 / 365
74 / 827 / 375
75 / 853 / 387
76 / 882 / 400
77 / 908 / 412
78 / 937 / 425
79 / 963 / 437
80 / 992 / 450
81 / 1,019 / 462
82 / 1,047 / 475
83 / 1,074 / 487
84 / 1,102 / 500
85 / 1,135 / 515
86 / 1,168 / 530
87 / 1,201 / 545
88 / 1,235 / 560
89 / 1,279 / 580
90 / 1,323 / 600
91 / 1,356 / 615
92 / 1,389 / 630
93 / 1,433 / 650
94 / 1,477 / 670
95 / 1,521 / 690
96 / 1,565 / 710
97 / 1,609 / 730
98 / 1,653 / 750
99 / 1,709 / 775
100 / 1,764 / 800
101 / 1,819 / 825
102 / 1,874 / 850
103 / 1,929 / 875
104 / 1,984 / 900
105 / 2,039 / 925
106 / 2,094 / 950
107 / 2,149 / 975
108 / 2,205 / 1,000
109 / 2,271 / 1,030
110 / 2,337 / 1,060
111 / 2,403 / 1,090
112 / 2,470 / 1,120
113 / 2,536 / 1,150
114 / 2,601 / 1,180
115 / 2,679 / 1,215
116 / 2,756 / 1,250
117 / 2,833 / 1,285
118 / 2,910 / 1,320
119 / 2,999 / 1,360
120 / 3,087 / 1,400
121 / 3,197 / 1,450
122 / 3,306 / 1,500
123 / 3,418 / 1,550
124 / 3,528 / 1,600
125 / 3,638 / 1,650




Speed rating
The speed symbol is made up of a single letter or an A with one number. It indicates the maximum speed at which the tyre can carry a load corresponding to its Load Index.

Code / Mph / Kmh(Not all apply to our vehicles...)
A1 / 3 / 5
A2 / 6 / 10
A3 / 9 / 15
A4 / 12 / 20
A5 / 16 / 25
A6 / 19 / 30
A7 / 22 / 35
A8 / 25 / 40
B / 31 / 50
C / 37 / 60
D / 40 / 65
E / 43 / 70
F / 50 / 80
G / 56 / 90
J / 62 / 100
K / 68 / 110
L / 75 / 120
M / 81 / 130
N / 87 / 140
P / 94 / 150
Q / 100 / 160
R / 106 / 170
S / 112 / 180
T / 118 / 190
U / 124 / 200
H / 130 / 210
V / 149 / 240
Z / >149 / >240
W / 168 / 270
(W) / >168 / >270
Y / 186 / 300
(Y) / >186 / >300

[lmoengnr]

Interesting info, thanks for sharing.

[MR_VX]

This is a very good read thanks

[rb26dett]

Excellent post, very informative.