DISCLAIMER
TyreSafe makes every effort to provide accurate pressure information. However, the accuracy of data cannot be guaranteed and users should consult their handbook for full approved settings. Please ensure your caravan’s MTPLM, number of wheels and tyre size have been inputted correctly before inflating your tyres to the suggested pressures. If in any doubt, please ask your vehicle manufacturer or consult with a TyreSafe recommended tyre dealer.
How do I check the pressures on my caravan or car trailer?
We have more detailed advice specific to this topic here: Caravan and trailer tyres often require higher inflation pressures than are required for the same tyres on a car. It is essential to identify and maintain correct tyre pressures. In the absence of any recommendation in the vehicle handbook regarding car tyre inflation when towing, increase the towing vehicle’s rear tyre pressures by 4 to 7 psi (0.3 to 0.4 bar) to improve the stability of the complete unit.
Checking the pressures on your caravan tyres
Whatever tyres are fitted to the towing car and caravan or trailer tent, it is essential to the safety and stability of the combination that all tyres are correctly inflated for the applied loading. This is a golden rule of motoring and of caravanning in particular. Under or over inflated tyres can not only adversely affect the handling, but can also lead to dangerous tyre failure.
Tyres not inflated to the correct pressure wear out more quickly. So in the long run, keeping them at the right pressure could also save you money.
When should I check the pressures on my caravan tyres?
You should check and adjust the pressures on your caravan tyres prior to any journey, when the tyres are cold. Checking your pressures during or after a run will not give an accurate reading, and pressures are likely to drop when they cool down. After pressure checking ensure the valve is not leaking and the valve cap is fitted.
Where can I find out the correct pressures for my caravan tyres?
The correct inflation pressure for your car tyres will be found in the car handbook and in some cases on a placard displayed on the vehicle. In the absence of special towing recommendations, in order to improve handling and accommodate the additional load on the hitch, the rear tyres should be set at the “fully laden” pressure. Where full load pressure does not differ from that for normal driving the rear tyre pressure should be increased by 4 to 7 psi (0.3 to 0.5 bar).
For your caravan/trailer tent tyre inflation pressures, follow the manufacturers’ recommendations which can normally be found in the handbook. In the absence of this information, seek the advice of the tyre manufacturer, use our caravan pressure checker https://www.tyresafe.org/caravan-tyre-pressure/
or see the below tables for suggested tyre inflation pressures and maximum axle loads.
Axle Load and Inflation Pressure Tables
The extraordinary demands placed on tyres fitted to caravans mean that, in the interests of safety, it is prudent to avoid continuous operation at or approaching the tyres’ maximum load capacity. Accordingly, the UK tyre industry strongly recommends that the maximum vehicle load should not exceed 90% of the combined tyre load capacity as indicated by load index. The tables overleaf show maximum recommended axle loads along with suggested tyre inflation pressures for some sizes. The maximum permissible axle loads are shown in red. (The loads shown assume two tyres per axle).You can also use TyreSafe’s unique caravan tyre pressure calculator at www.tyresafe.org. Input your caravan’s Maximum Technically Permissible Laden Mass (MTPLM), the number of wheels and your tyre size and type. The calculator will then give you a suggested inflation pressure.
Remember the ‘Golden Rules’For safe towing of caravans and trailer tents:
- Fit the correct tyres
- Tyres must be in good condition
- Tyre pressures must be correctly maintained using an accurate tyre pressure gauge
- Do not overload
Glossary of Terms
Bonus Load – Is the additional load permissible (at an increased tyre pressure) when running at a reduced maximum speed of 100 km/h where the gross weight (MTPLM) does not exceed 3.5 tons with a tyre speed symbol of at least L.
Service Description – Is the combination of the tyre’s Load Index (LI) and Speed Symbol (SS) moulded into the sidewall of the tyre in the vicinity of the size marking.
Load Index – Is a numerical code associated with the maximum load a tyre can carry at the speed indicated by the Speed Symbol. (See table on page 8)
Speed Symbol – Indicates the maximum speed at which the tyre can carry a load corresponding to its Load Index. (See table on page 8)
Safety Type Rim – A wheel rim incorporating a hump or flat ledge on the outer bead seat to reduce the risk of possible tyre dislodgement.
Pre-Puncture Sealant – A solution applied to the inside of the tyre at the time of fitting to prevent air loss in the event of a puncture. (Not recommended by the tyre industry).
Post-Puncture Sealant – A liquid applied via the tyre valve following a puncture, which seals the penetration hole. (The tyre industry recommends these as a ‘Get you home’ measure only).
MTPLM – The Maximum Technically Permitted Laden Mass of the caravan/trailer tent. (Formally referred to as the maximum gross or authorised weight).
MIRO – The Mass in Running Order of the caravan/trailer tentwhen equipped to the manufacturer’s standard specification. (Formally referred to as the unladen or ex works weight).
User Payload – The difference between the MTPLM and the MIRO.