I have a year 2000 Elddis Typhoon XL caravan. the hitch has been changed from the 50mm English anti-sway system to a 17/8" AL-KO one with a standard height ball. My vehicle, a Ssang Yong Rexton the ball height is 450mm and when our horse float is attached it is almost perfectly level and tows like a dream. However when my 'van is attached it is very obviously down at the back and at around 85kph, especially downhill it starts to sway. If I measure the hitch height on the 'van when it is level it is 380mm. Is this the cause and if so should I have a new towing tongue made of correct height, to accommodate the 50mm long neck ball and refit the English hitch? Any advise will be gratefully received, thank you.
The EC Directive 94/20/EC (The standard that all towbars are designed to) states that the tow ball height should be between 350 and 420mm from the ground with the vehicle in a 'laden' state.
What is the towball weight of the van. Its is more likely to cause sway having it too light than hitch height. My tow ball is about 450mm (laden) and my van (around 1400kg full)) tows nicely with just 70kg on the ball (Although I prefer to run 90kg -100kg. )
Alko have a max ball weight of 100kg.