Tyre Sidewall Markings

Book your service

 

Have you ever wondered what all those numbers and letters are on the sidewall of your tyre mean? There is probably a lot more information on a tyre sidewall than you realise.

Firstly it helps to identify the tyre size and its specification, secondly, it is to show that the tyre has been tested to European standards. If you see the letter ‘E’ then you can be assured that the tyre meets the necessary European legislation. According to guidelines, it is not illegal to purchase tyres with a lower/higher load capacity of speed rating but it is not recommended to do so. If you are at all unsure then refer to your handbook or speak to us and we will be happy to assist you.

A common size is a 205 55 R16 91W so here is a brief guide to what all the numbers and letters mean:

  • 205- Is the total width of the tyre in millimeters
  • 55 – The ratio of the complete tyre width as a % of the overall width of the tyre.
  • R 16 – This relates to the specific diameter of your wheel in inches
  • 91 – Is the load index rating of that particular tyre, in this case a load index of 91 can carry a total weight of 615kg.
  • W – When at full load this shows the tyres speed rating.

Higher Load Indexes and Different Speed Ratings –

It is possible to carry out fitting a tyre with a higher load index and a different speed rating to those highlighted in your vehicle handbook. It should be noted that this can cause increased fuel consumption and may cause tyre failure, it can also cause cracking or a blow out. If you are at all unsure then we advise you check with us here at Phillips Tyres to ensure they are permitted under the regulations and that they do not rise above the required specifications.

Tread Wear Indicators (TWI)

These are the small blocks molded into the tyre tread, that allows you to see when your tyres are getting close to the minimum legal tread depth.

The sidewall also shows you the week and year that your tyre was manufactured.

If you require any guidance then please contact us here at Phillips Tyres and we’ll be more than happy to assist in allowing you to have complete peace of mind.