Most caravan owners know that it is critically important to have safe and legal tyres. Yet each year many serious accidents occur and numbers of caravans are destroyed because this most obvious fact is overlooked. The reason why caravan tyres are frequently overlooked is that they are often half hidden under the caravan. Few people pay much attention to their tyres anyway. Also it is not easy to interpret the sidewall markings to ascertain the date of manufacture to see if the tyres are too old. Additionally it is not easy to maneuver a caravan in and out of a tyre depot. etyres mobile service answers all these difficulties because we come to you. We are fully conversant with all aspects of supplying and fitting caravan tyres. And we do this with our mobile tyre fitting vans at your selected location.
Most caravans are fitted with 13 inch tyres but 14 inch tyres are now being widely used on new models. The reason for this is twofold. Firstly the larger sizes of caravan tyres provide additional stability and secondly, as most tyre retailers do not carry large stocks of caravan tyres they, perfectly correctly, satisfy orders by using regular commercial tyres which do not frequently occur in 13 inch. The same applies on the Continent where specialists who sell caravan tyres are few and far between. Common sizes of caravan tyres are 175/80/13c (8 ply), 165/80/13c (8 ply), 155/80/13c (8ply) and 185/65/14c (8ply).
Unless a lot of touring miles are covered it is unlikely that you will wear out your caravan tyres. Like any other tyres caravan tyres deteriorate with age. Organisations such as the Tyre Industry Council and the British Rubber Manufacturers’ Association advise a caravan tyre life limit of between seven and ten years. However after as little as five years caravan tyres can become distorted if they are left unused in the same position. Also surface cracking of the sidewalls can occur if the tyres are allowed to become under-
Caravan tyres, like all car or light commercial tyres must have a minimum tread depth of 1.6mm in order to be legal and roadworthy. However, due to the infrequent use and low mileage of many caravan tyres it is good practice to consider replacing them after five years, regardless of the amount of remaining tread. At the end of this section we include a paragraph entitled “Manufacturing dates of caravan tyres”. This is designed to assist you in reading the sidewall marking of your caravan tyres. This shows how to establish the date of manufacture.
In some European countries the minimum tread depth for all car, light commercial and caravan tyres is 2mm. So it is possible to drive legally as far as the boarder of a neighbouring country only to become immediately illegal as soon as you drive on foreign roads. Prior checking of your caravan tyres is therefore vital.
Sidewall impact damage of caravan tyres is quite common because of the relative ease with which kerbs can be clipped while towing. The high stress loading when a sidewall impact occurs causes the plys of the tyre sidewall to delaminate. This is sometimes, but not always, visible if air escapes and forms a bubble between the plys. The invisible damage is obviously of greater potential danger. During cornering the load on caravan tyres can be up to 1? tonnes. For motor caravans the load factor can even be as high as 3 tonnes. So it is not surprising that sidewall impacts can easily cause irreparable damage. A bulge in the sidewall of any tyre cannot be repaired and calls for immediate replacement.
All caravan tyres are designed to carry a specific load or weight, an overloaded tyre will quickly overheat. This greatly increases the risk of the tyre blowing out. For single axle caravans this is particularly dangerous. The Load Index is shown on the sidewall of all caravan tyres immediately behind the size coding and in front of the speed letter code. A typical example will be:-
175 is the tyre width in millimeters, 80 is the sidewall height, expressed as a percentage of the width.R indicates a radial type construction.13 is the wheel diameter in inches.97 is the Load Index. T is the speed rating. The load rating is a very important factor with all caravan tyres. It is not sensible to compromise by fitting a regular car tyre instead of a properly load rated caravan tyre.
In fact in most cases this is actually false economy because there is little or no difference in price. The compromise often occurs because the correct tyre is not available. Ordering from etyres overcomes this problem. To be legal, and safe, a single axle caravan must have tyres designated as suitable to carry at least half of the maximum allowable weight or Technically Permissible Laden Mass (MTPLM). The Load Index number represents the tyre maximum weight limit in kilograms. A pair of car tyres index coded 79 may not used on a caravan having a MTPLM in excess of 874 kg.
Over the last few years there have been a number of reports of caravan tyres disintegrating in service. This has been more common on heavy caravans and often when the caravans had been used in southern Europe during the summer. This suggests the tyres may have been running very hot at some time in their life. The inference being that if you are covering long distances in high temperatures it is a good precaution to stop for rest periods to allow your caravan tyres to cool.
Before every trip
Check the manufacturing dates of your caravan tyres. If they are over five years old consider replacing them.
Inspect your caravan tyres for cuts, sidewall cracking or imbedded objects. This includes the inner sidewalls.
Check the pressures of all your caravan tyres, including the spare.
Check the pressure of the tyres of the towing vehicle. Some vehicle manufacturers specify slightly high rear tyre pressures when towing.
Check the tread depths. If this is less than 3mm consider replacing, particularly if you are planning a long trip.
Check caravan wheel bolt tightness with a torque wrench.
Check jack operation. Most jacks benefit from a drop of oil on the screw mechanism. As caravans are frequently parked off road, have a suitable piece of board available to prevent the jack from sinking into soft ground.
Manufacturing dates of caravan tyres
Date of Manufacture is shown on the sidewall of all caravan tyres as part of the DOT (U.S. Department of Transport) code found close to the wheel rim. Example of a code is DOT A87C DEF 699, the final set of three, or four, numbers being the date code. Tyres made between 1990 an 1999 use a three digit code followed by a triangle and indicate the month and year in which the tyre was made (699 being June 1999). From 2000 onward a four digit code is used to show the week and year (0102 being the first week of 2002). A small number of tyres may not have the DOT code but in these cases the date of manufacture may still shown elsewhere on the tyre, for instance if you see as a separate group of letters 4202 that is definitely 42nd week of 2002.