Caravan World — 10 June 2009

…following our towing myths special, John provides us with more food for thought.

“It has been proven that by placing just four cases of wine at the back of the van, the stability of the van is reduced by as much as 10 per cent.”

MYTH: You need to accelerate to correct a swaying trailer.

False. This is something that my father used to swear by, but when I remember back it never ended well. The best thing is to take your foot off the accelerator, and brake gently till the car and trailer combination have come to a complete stop. Try to find the cause before moving off again. Common causes are: incorrectly loaded trailer, flat tyre on trailer.

MYTH: You should always travel with your water tank(s) full.

True. The water tank(s) in your caravan are generally centred around the axle(s) and fitted underneath the van, so by travelling with them full, it lowers the centre of gravity of the van, making it safer to tow. Because the water tanks fitted to vans do not have baffles in them, the water is free to move from side to side if the tanks are half full, which may contribute to sideways movement of the van. So make sure the tanks are full. Mind you, this does increase the tow vehicle’s fuel consumption somewhat.

MYTH: I can carry extra weight on the drawbar if I counter the weight by loading more stuff at the back of the van.

False. This one is tricky, because you can fit extra stuff on the drawbar as long as it is within the caravan manufacturer’s specifications, so check with them first, and secondly ensure the extra weight doesn’t exceed the towball capacity of the vehicle. Now, when you try to counter the weight by placing items down the back of the van to compensate for the load up front, this sets up a problem that is termed yaw inertia – i.e., you have two weights separated by the length of the van. These act like a pendulum in the horizontal plane, and as the van moves about as it travels along the road surface, these weights may gain sideways momentum and could eventually lead to uncontrollable trailer sway. You can reduce the likelihood of this by centring the load around the axle(s).

It has been proven that by placing just four cases of wine at the back of the van, the stability of the van is reduced by as much as 10 per cent.

MYTH: I don’t need towing mirrors; I have a camera fitted on the back of my van.

False. Towing mirrors are required in almost all cases when you tow a caravan. A camera is a great addition to any arsenal of towing equipment, but it should be used in addition to a good set of mirrors, not instead of. A good set of mirrors will enhance your ability to manage traffic. Next time you hook your van up to the car, drive in a straight line for about 30m, then stand at the back corner of the caravan and look down the side of the van toward the car, if you can’t see all of the mirror, then you will have reduced visibility to the rear when towing and in my opinion you may be compromising your safety.

MYTH: I heard that I should store my van with the water tanks full.

True. By storing your van with the water tanks full, you will reduce the likelihood of mould and mildew and algae growing in the tank, especially if you drop in one or two Puritabs prior to storage. When you go to use the van, drain the water from the tanks and use it to water the lawn, then refill the tanks with fresh water ready for use.

MYTH: My mate told me that I should maintain my speed when being overtaken by a truck.

True. When being overtaken by any large vehicle, the air that is displaced by that vehicle has the potential to upset the caravan. To reduce the likelihood of this happening, you should maintain your speed, which in effect stretches out the vehicle/van combination and keeps the van under control. If you feel you wish to exercise more control over the van, you could apply a small amount of braking force via the electronic brake controller manual override.

MYTH: I don’t need a weight distribution system; I can just beef up my rear suspension to carry the towball weight.

False. Generally speaking, when you hook up your caravan and the back of your vehicle drops more than about 25mm, then you should fit an appropriately-sized weight distribution system. The exception to this rule is if the vehicle manufacturer has stipulated that a weight distribution system is not to be used. Beefing up the rear suspension will help carry the weight, but it does nothing to counteract the lever effect that the towball weight has on the front wheels of the vehicle. By fitting a weight distribution system, the lever effect is negated and the weight is effectively placed back onto the front wheels.

…Other towing experts dispel and prove more towing myths in our towing myths special.


Towing myths feature John Eggenhuizen Tow-Ed Getabout Training Services safety

External Links