Looking at the sidewall of a caravan tyre, you will see the size markings – e.g. 195/70R15, but also the load rating which normally looks something like:

• 110S   (or)
• 112/110S

110S – This is the maximum weight that tyre can carry. In this case, this tyre can carry 1,060kg (see table below)

(On some light truck tyres, the load index is broken up into two ratings divided by a forward slash (112/110S). This is because the light trucks these ratings are used for often have dual tyres on their rear axles. The first number indicates the load carrying capacity if the tyre is for a single-tyre axle, and the second number applies to a dual-tyre axle. Interestingly enough, the capacity for a dual wheel setup is always less – the reason is to maintain reserve capacity if one of the tyres fail. If this were to happen, it would leave the sole remaining tyre  supporting the entire load. In the example above, for a single-tyre axle is 1120kg, and for a dual-tyre axle it is 1,060kg).

The speed symbol (in our example ‘S’) indicates the maximum speed at which the tyre can carry that specified load – in our case 180 km/h.

If a tyre does not list a profile - e.g. 195R15C  (it its NOT shown as  195/80R15C)  the default profile is 80.