Overhung Caravan Hitches
Tow vehicles pull conventional caravans towed via a hitch that overhangs that tow vehicle. Overhung caravan hitches, however, are inherently unstable. Side forces on caravans cause swaying. Such forces are not just undesirable. They are dangerous at speed. Moreover, they are even more dangerous at high speeds. Overhung caravan hitches cause (not just allow) these effects. Furthermore, the longer that overhang, the worse the effect. This article explains why overhung caravan hitches cause problems. Furthermore, it shows how you can reduce problems. You cannot, however, eliminate them.
This interaction is described in Why Caravans Roll Over.
Caravan and tow vehicle swaying is ‘fuelled’ by the rig’s weight and speed. The resultant side forces distort the tow vehicle’s rear tyres. Nevertheless, those tyres must maintain full intended grip. If that grip distorts, that can cause the vehicle to jack-knife. If that happens the rig may overturn. Moreover, many do.
This effect is speed-related. There are many other known causes. These include inadequate tow ball mass, excess caravan length and rear-end loading. Contrary to common-belief, weight distributing hitches may worsen the effect. They reduce cornering power by a typical 25%.
A weight distributing hitch is only necessary when towing a caravan that is really too long and/or too heavy for the tow vehicle. It has no plusses as such.
Avoid excess overhung caravan hitches
A few tow hitches are claimed easier to couple and uncouple. Some, however, increase tow hitch overhang. This is never desirable. Moreover, it inherently decreases towing stability.
You can reduce overhung hitch undesirable effects but you cannot totally eliminate them. The only truly stable caravan is the fifth-wheeler – as it the tow hitch directly above the tow vehicle’s rear axle. By doing so, it eliminates overhung hitches’ inherent instability.
RV Books provides a full explanation in our Why Caravans Rollover – and how to prevent it. This book explains just why caravan rollovers happen. Moreover, it shows how your own rig’s stability. Furthermore, it shows how to improve that stability.