Load and speed ratings
The load index:
A numerical code that corresponds to the maximum weight a tyre can support.
The speed rating:
A code that corresponds to the tyre’s maximum speed.
Locate the number and letter on the sidewall of the tyre and compare it with a load index table. Both markings always appear together adjacent to the tyre size markings.
Remember: These indices apply to tyres that are in good condition and do not apply if tyres are damaged, underinflated, overloaded or repaired. Check the vehicle handbook to find the recommended load index speed rating for the vehicle and stick to them.
Manufacturer specific markings
Vehicle manufacturer specific markings indicate that a tyre has been fine tuned to meet the specific performance needs of a particular vehicle or range of vehicles. It is important to ensure any new tyre you fit has the same markings.
1) Tyre width in millimetres
2) Aspect ratio – height of the sidewall as a percentage of its width. In this example, it is 55% of 205mm
3) Type of construction – “R” indicates radial
4) Diameter of the tyre rim in inches
5) The maximum weight capacity and running speed of a tyre according to the official load index and speed rating. In this example the load index figure of 91 is a weight of 615kg and a speed rating of V means the maximum vehicle speed is 149.1mph
6) E mark indicating the tyres have been tested and meet European standards
7) “DOT” code indicating tyres meet US regulations. Not significant in the UK
8) Date of manufacture – the first two numbers represent the week and the last two represent the year
9) Tubeless tyre construction (where applicable)
10) Direction of rotation – indicated by the arrow (applicable to directional tyres only)
11) Outer/Inner – refers to the fitting of asymmetric tyres. Tyres must be fitted according to these markings due to the differing tread patterns on the inner and outer sides
12) Mud and snow tyres
13) Uniform Tyre Quality Grading Markings, required by USA consumer information regulations (not required in the UK)
14) Location of Tread Wear Indicators (marking not on all tyres) – Tread Wear Indicators moulded into the base of the tread are set at the minimum legal depth of 1.6mm
