If you couldn't go over 40 mph without snaking there must have been something wrong with the outfit. Possibly the trailer and load were too heavy for the car, incorrect tyre pressures on the car or trailer, incorrect nose weight etc or a combination of these things all add up to cause instability.
If you match the outfit carefully, load carefully and drive smoothly then it should be possible to drive up to the speed limit without problems. Obviously things like sidewinds and the buffeting from passing vehicles need to be taken into account as well.
What are you going to be towing with? If you are using a Disco I expect you will need a B+E licence. Check the kerbweight of the tow car and aim for a caravan with an MTPLM around 85% of that unless the car has a lower max tow limit.Check tyre pressures, noseweight etc and you should be fine.
Have you got a B+E licence? You'll need B+E for that sort of outfit but be aware that twin axle caravans are not always welcome on European sites, sometimes they are not allowed and sometimes the pitch fees are much higher than for single axle vans.
If you have a Discovery then that is an excellent towcar. For your trip buy a modern single axle caravan up to about 1500kg max weight. If you are an experienced Hgv1 driver then you know how to load a trailer properly so load you caravan properly around 90-100kg noseweight. Obviously you will set tyre pressures correctly. Your motorway speed limit in France & most other European countries is truck speed 55mph/90kph. It will tow straight as a die for as far as you like.
I have a twin axle caravan and I have never been refused entry to a site or been asked to pay more.
You do occasionally see notices prohibiting twin axles but if you ask I have always been allowed on site. It seems that the notices are to discourage a certain type of traveller.
DaveS1
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