COMMERCIAL VEHICLE TYRE DATA - tyre markings
Commercial vehicle tyre marks explained
Truck tyres have two main types of markings on their sidewalls in addition to the manufacturer's own marks.
TYRE SIZE MARKINGS
Tyre size markings include a references to the following information
- the section width of the tyre (either in inches of millimetres)
- the types of tyre construction and the rim diameter in inches
- there is often a reference to the 'aspect ratio' of the tyre - that is a ratio of the tyre's height compared to its width.
| tyre size marking example 1: | |
| 11R22.5 | |
| 11 | 11 inches section width |
| R | radial construction |
| 22.5 | rim diameter 22.5 inches |
| tyre size marking example 2: | |
| 295/80R22.5 | |
| 295 | 295mm section width |
| 80 | low profile tyre - section height 80% of its section width |
| R | radial construction |
| 22.5 | rim diameter 22.5 inches |
LOAD AND SPEED MARKINGS ON COMMERCIAL TYRESThese markings are linked together because they are inter-related. They are known as the 'Load Index' and the 'Speed Rating Symbol'. Load index is a numerical code which shows the maximum load a tyre can carry at the speed shown by it Speed Rating Symbol. The index is usually given for both single and twinned tyres. The Speed Rating Symbol indicates the speed at which the tyre can carry a load shown by it Load Index. |
|
| tyre speed rating example: | |
| 112/110M | |
| 112 | = Load Index for single tyres |
| 110 | = Load Index for twinned tyres |
| M | = Speed Rating |
