The National Caravan and Recreational Vehicle Towing Guide

Towing your Caravan

The loaded mass of your trailer must not exceed:

• the capacity of the towbar; or
• the maximum towing mass specified by the tow vehicle’s manufacturer; or
• the maximum ball weight specified by the tow vehicle’s manufacturer.

The Driver

Apart from adding to the driver's legal responsibilities, towing requires a greater degree of knowledge and skill than normal driving. When towing, you should:

• allow for the extra length and width of the trailer when entering traffic;
• apply the accelerator, brakes and steering smoothly and gently to avoid sway, especially in wet or slippery conditions;
• maintain a space of at least 60 metres between you and the vehicle in front to allow for a longer stopping distance;
• engage a lower gear in both manual and automatic vehicles to increase vehicle control and reduce brake strain when travelling downhill;
• allow more time and a greater distance in which to overtake. When towing, your vehicle's capacity to accelerate is reduced;
• if possible, reverse with a person watching the rear of the trailer;
• where areas are provided, pull off the road to allow traffic building up behind you to overtake;
• be aware that towing is more stressful than normal driving and is more likely to cause fatigue. Therefore, more rest stops should be planned.

Caravan Sway

If your caravan begins to sway or snake, remain calm and avoid the urge to apply the towing vehicle’s brakes. Don’t try to steer out of the swaying / snaking. Alternatively hold the vehicle steady and try to stay in the lane. Gently apply the caravan’s electric brakes using the manual control in the tow vehicle. Otherwise, where conditions permit, continue at a steady speed or accelerate slightly until the sway stops.

When a condition of sway has been corrected, slow down and pull off the road safely. Check that your load is correctly distributed within the trailer, making sure that heavier items are placed over the axles of the caravan. A caravan that doesn’t have the load distributed correctly may not handle well and may be the cause of swaying / snaking.

Loading Trailers

It is important not to overload your trailer. You should not exceed the maximum load specified or recommended by the trailer manufacturer, nor should you exceed the tyre or coupling capacity. Trailers now have attached to their drawbar or body a plate displaying the ATM which is the maximum allowable weight.

For safety and ease of towing the ball mass (the mass towards the front of the trailer carried by the tow ball of the towing vehicle) should be about 10% of the total laden trailer weight. The ball mass can be measured either at a weighbridge by resting only the jockey wheel on the scale, or by placing a ball mass scale under the coupling then taking the weight off the jockey wheel. Depending on capacity, bathroom scales can also be used.

Weight Distribution Hitches

The trailer’s drawbar should preferably be level when being towed. Towing applies a downward force on the rear of your vehicle which is referred to as 'ball weight'. This weigh twill be carried by the rear suspension, which can cause the back of the tow vehicle to sag. In response, the front of the vehicle will rise and the steering will feel light, due to the lower weight on the front wheels. This can cause loss of steering and braking performance (increased wear and tear on the rear suspension and tyres will also result).

Weight distribution hitches will help return your vehicle close to the original dynamics by re-distributing the effects of this ball weight to the original balance between front and rear suspensions, thus levelling out the vehicle/trailer combination.

Some vehicle manufacturers require the use of a Weight Distribution Hitch to be able to tow to their stated maximum capacity. You are legally obliged to use them in such situations. A few vehicle manufacturers however prohibit their use.

Remember Weight Distribution Hitches are not a means of lowering the ball weight, and you still cannot tow more than the maximum ball weight as set out by the vehicle/towbar manufacturer. You should always consult your vehicle owner’s manual for the true towing capacity of your vehicle and match that with the correct towbar.

Fitting of weight distributing hitches is not recommended with over-ride brakes, as the hitch interferes with the application and release of the brakes, and may cause brake malfunction. Neither should they be used in extreme off road conditions.

Sway Control

When the weight of a loaded caravan or trailer is transferred via the towball connection to the tow vehicle suspension, a Weight Distribution Hitch, matched to the towball weight is the first essential for sway control. This restores the tow vehicle front wheel traction and tow vehicle stability.

External factors such as cross winds and overtaking trucks and buses create significant side thrust forces that increase in intensity with increasing caravan/trailer size and load. If these forces are noticeable after fitting an appropriate Weight Distribution Hitch, an added sway control unit should be fitted.

Below are three examples of Sway Control devices that are commercially available: