Typical examples of this, shown on the right are 205/60R16, P205/60R15, LT285/70R17 and ST205/75D15.
In all of these cases the first set of 3 digits is the width of the tire, measured from sidewall to sidewall, in millimeters.
They can be sized with no letter before the size, P-metric, LT-metric and ST, and can have a B, a D or an R later in the size.
We will explain that afterwards, but first for the meaning of the numbers.
The image below shows a tyre which was made in the eleventh week of 2011..
Metric Sizing: The vast majority of tires sold today and sized by the "metric" system.
Your tire’s load index tells you its maximum carrying capacity.
It’s important to choose a replacement tire that fits with your manufacturer’s recommendations.
A tyre with a speed rating of V, for example, has a maximum speed of 240km/h.
All the important information you need to know about your tire is printed on the sidewall.
We tend to assume that tyres need changing when the tread depth begins to threaten the annual MOT test.
This works for our car tyres, but the caravan is a different matter.
It’s important to choose a replacement tyre that fits with your manufacturer’s recommendations.