LOAD INDEX & SPEED SYMBOLS

On the sidewall of all tyres you can find the Load Index and Speed Symbol for that tyre (following the key sidewall markings) for example 105 S.
LOAD INDEX

The load rating (represented by the numerical value) is related to the maximum weight that tyre can carry. So in this case 105 would refer to a load capacity of 925kg, with most passenger vehicle load indexes range from 62 to 126.
Load index Load in Kg per tyre Load index Load in Kg per tyre Load index Load in Kg per tyre Load index Load in Kg per tyre Load index Load in Kg per tyre
62 265 75 387 88 560 101 825 114 1180
63 272 76 400 89 580 102 850 115 1215
64 280 77 412 90 600 103 875 116 1250
65 290 78 425 91 615 104 900 117 1285
66 300 79 437 92 630 105 925 118 1320
67 307 80 450 93 650 106 950 119 1360
68 315 81 462 94 670 107 975 120 1400
69 325 82 475 95 690 108 1000 121 1450
70 335 83 487 96 710 109 1030 122 1500
71 345 84 500 97 730 110 1060 123 1550
72 355 85 515 98 750 111 1090 124 1600
73 365 86 530 99 775 112 1120 125 1650
74 375 87 545 100 800 113 1150 126 1700

In all instances the tyres load index must meet or exceed the value displayed on the vehicles placard.

SPEED SYMBOL

The speed category symbol, for example 'S', indicates the maximum speed at which the tyre can carry a load corresponding to its load index. So in this case, 'S' would refer to a maximum speed of 180km/hour
See the chart below for a full list of speed symbols and their applicable values.
Speed Symbol J K L M N P Q R S T U H V W Y VR ZR
Speed in kmh 100 110 120 130 140 150 160 170 180 190 200 210 240 270 300 >210 >240

*A tyre with ZR symbols have a speed capability of over 240km/h. Your T-Mart can always consult with the tyre manufacturers to ascertain the tyres actual speed capabilities.

The legal speed symbol requirements vary by state, please check with your local T-Mart.


PLY RATING

Ply ratings identify the load carrying capacities of a tyre in terms of plies. Ply rating originally referred to the number of cotton layers used to strengthen a tyre's casing. Today, when tyres are labelled 10-ply for example, they are no longer actually constructed of 10 individual layers of cotton, but they do offer the equivalent strength. Over time, steel ply and radial construction replaced cotton, leading to a new distinction: Load Range. Load Range identifies the maximum amount of weight that can be placed on a tyre horizontally, which varies depending on tyre size and inflations limits.