Choosing the correct tyre

As a general rule, replacement caravan tyres should be chosen to be of the same full service description as those previously fitted. However, there are a number of situations where this might not be the case:

• the original specification of tyre is no longer available
• the original specification of tyre was inadequate
• the payload capacity of the caravan has been increased
• the caravan wheels have been changed to ones of a different size (normally the fitting of alloy wheels)

If you find yourself in any of these circumstances when choosing a replacement caravan tyre, follow our simple checklist.

1. Identify the nominal wheel diameter, tyre size, and maximum caravan weight.
2. Select suitable tyres with a full service description to match this wheel diameter, have a load index sufficient for the maximum weight of the caravan (taking into account whether the caravan is a single or double axle), and have a speed symbol of at least ‘M’ (81mph) or higher.
3. Eliminate any tyre options where the maximum weight of the caravan exceeds 90% of the load index value.
4. If the section width differs slightly (eg 185 compared to 175, say) then they are likely to be compatible, unless the clearance between the wheel and the wheel box is particularly small. Try jacking up the caravan wheel to assess the clearance as the wheel moves within the wheel box, if unsure.
5. If the section width differs significantly to that previously fitted, and/or if the rim width has been changed from the original specification, check not only that the tyres are compatible with the wheels, but also that their section width and overall diameter fit within the wheel box.
6. Unless specified by the caravan manufacturer, do not choose an extremely low profile tyre.
7. Do not choose a commercial grade (‘C’ suffix) tyre unless the load and speed requirements demand it, and a ‘car type’ tyre is not available which can satisfy these.

Identifying the correct inflation pressure

Inflation pressure is an important issue – the safety and durability of your caravan tyres depend on them being inflated correctly. Incorrect inflation pressure can adversely affect the handling of the caravan and can also increase fuel consumption.

For any given tyre, there will be an optimum inflation pressure based on the load it is carrying. Since caravans generally operate at, or reasonably close to, their maximum weight, it is sensible to choose the optimum pressure for that load condition. If your caravan is used significantly below its maximum weight, however, you can choose an optimum inflation pressure for its actual laden weight. We strongly recommend that you should confirm the caravan’s actual laden weight in its intended loading condition on a weighbridge.

Commercial grade tyres are designed to operate over a wide range of loads and can differ when used on a caravan. For example, a tyre with a maximum inflation pressure of 54psi at its maximum load may only require a pressure of 30psi when used on a caravan.

Refitting a wheel

If a wheel has been removed for servicing or to replace a puncture – we recommend you follow the correct procedure when refitting the wheel.

1. Ensure that the mating surfaces between the wheel and hub are clean and dry.
2. Ensure wheel nut/stud threads are clean and dry with no rust or paint flakes on the thread or seats. Be cautious of lubricating the threads of wheel nuts or bolts. Tightening torques are usually specified ‘dry’ and any lubrication may require an alternative torque setting to be used, or damage may result.
3. Hand-tighten all nuts/studs to centre the wheel before using the wheel brace/torque wrench.
4. Use a diagonal wheel nut tightening sequence to ensure that the wheel seats onto the hub without misalignment.
5. Do not over tighten wheel nuts/studs. Adhere to the tightening torques as recommended by the caravan manufacturer or chassis supplier. We do not recommended you fully tighten nuts or studs using air-powered equipment. This can over tighten and damage threads. If you suspect that nuts/studs have been over tightened, they should be replaced.
6. We recommend you should finish tightening by using a torque wrench set to the figure stated in the caravan operating manual. Do not use the corner steady brace which is only designed to raise or lower the corner steadies.
7. After a wheel has been refitted, always recheck the torque after 20-30 miles use or 20-30 minutes travelling. Even if properly torqued up, it is occasionally possible for fixings to loosen should the wheel ‘bed in’ on the hub.

Making sure your tyres are legal

It is an offence to mix cross-ply and radial tyres on the same axle.

We strongly recommended that aspect ratios are also matched (80 and 82 can be counted as the same), as should ply ratings or load index values on the same axle, although these are not legal requirements. Mixing different makes of the same size or specification is OK.

Tyres must be correctly inflated, and free from certain cuts and other defects. They must have at least 1.6mm tread depth across the central three quarters of the tread breadth around the entire circumference of the tyre (depth of 20p piece outer edge). They must be of a suitable specification.

If a spare wheel and tyre is carried, it must also comply with all relevant regulations.

The maximum fine for each defective or unsuitable tyre is £2,500, plus 3 points on the driver’s licence.

Travelling overseas

As a general rule, if your vehicle meets the legal requirements for use in the UK, then it can be used across Europe without difficulty. An exception to this is the situation relating to tyres in France. Since on certain French motorways it is permissible to tow at up to 81mph (130kph), the French require that your tyres meet this requirement. This is only likely to be a concern with older caravans, but if in any doubt, check the specification of your tyres before travelling and read up on overseas driving regulations, since on-the-spot fines can be significant.