The sidewall symbol mystery – explained
Decrypting your tyre
The sidewall of a modern tyre contains a multitude of figures, letters and symbols which, to the untrained eye, it can appear to be completely confusing. And yet all of this information is valuable and necessary and in some instances very useful for the motorist.
Tyre wear indicators
For instance, you can tell the age of a tyre, and how you can check if a tyre is below the legal minimum tread depth, without the need for a tread depth indicator, these are the TWI (Tread Wear Indicators) which are blocks of rubber set in the tread at 1.6mm. if they are even with the tread, the tyre is illegal.
Tyre Sidewall Markings
The sidewall markings chart for a passenger car and van:
1. Tyre brand name
2. Pattern or model code
3. Tyre size
4. Service description (load index and speed symbol)
5. ECE or EEC type approval number (C&U regulations stipulate all tyres used in the UK must carry an E number)
6. ECE noise approval
7. North American recall number
8. Date of manufacture code. Four numbers, the first two determine the week of manufacture from 01 (January) to 52 (January) the second two the year of manufacture e.g. 03 (2003).
9. UTQG quality rating. An USA requirement, has no significance in the UK or Europe.
10. Maximum permitted load. A USA requirement, as above
11. Maximum permitted inflation pressure. A USA requirement, as above.
12. Denotes tubeless construction.
13. Safety warning.
14. Direction of rotation. (Directional or Composite tyres).
15. Rim fitment instruction (Asymmetrical or Composite tyres)
16. Denotes extra load tyre construction
16a Denotes reinforced tyre construction Position of tread wear indicators (TWI)