Advice Required for tyre sizes

[Bouldy]

Having just bought a 1992 Elddis Force 4 SL caravan I need help finding the correct rim and wheel sizes for the caravan. I'm told by Elddis that the Force 4 SL was a dealer special model and the manual I have with it does not have exact specs for the Force 4 SL.

The manual has 8 model specs in the general data section and the model Typhoon astrixed by someone. Its Wheel rim size is 5 HG 635 and Tyre size is a SuperVan 175c and 51psi tyre pressure. If this is the correct data can anyone make heads or tails of this info??

The current tyre fitted is a 185 R13C, but has little clearance between the tyre and wheel arch.

Please advise

 

[audiorob]

ELDDIS FORCE 4SL from Knowepark Caravans and Motorhomes, Livinston, Scotland

ELDDIS FORCE 4SL from Knowepark Caravans and Motorhomes, Livinston, Scotland

kpcm.co.uk

According to this link Knowepark caravans sold an identical model recently and is still shown on their website so may be able to advise? It was a special at the time so they might also confirm which model it was based on.

 

[Bouldy]

ELDDIS FORCE 4SL from Knowepark Caravans and Motorhomes, Livinston, Scotland

ELDDIS FORCE 4SL from Knowepark Caravans and Motorhomes, Livinston, Scotland

kpcm.co.uk

According to this link Knowepark caravans sold an identical model recently and is still shown on their website so may be able to advise? It was a special at the time so they might also confirm which model it was based on.

Thanks for the heads up ill contact them.

 

[chrisn7]

A modern tyre will have markings more like this: 185/70 R13 88T - this is just an example not a recommendation for your van.

185 is the tyre width; 70 is the tyre profile; 13 is the rim diameter in inches; 88 is the load index; T is the maximum speed rating.
The letter C indicates 'commercial' meaning that the tyre has more reinforcement than a standard car tyre. C is appropriate for a single axle van, twin axles usually have standard car tyres.

Therefore your currently fitted tyre appears ok size wise, so you need to check the load index requirement which is easy to do. Find the caravans maximum loaded weight - a 1992 van might show this as Gross weight, or Max weight or MAM all being earlier versions of todays MTPLM. This could be by the main door or on a plate on the A frame, or in the handbook.

Dividing this weight by 2 gives the load each tyre has to carry; now add 10 % to this. Go online and search 'tyre load index' - there are loads of tables available. Using your calculated weight value, read off the nearest index, going to higher rather then lower if necessary. The 10% + represents a safety margin in case of accidental overloading.

Many tyres this size have a T speed rating which is more than adequate. so now you have the tyre spec.

The gap between tyre and wheel arch is possibly due to the caravan rubber suspension ageing, rather than the wrong size rim