Optimising caravan nose weight is vital for safe towing. Caravan & Motorhome Books’s Collyn Rivers shows why, and how to know what it really should be. If you throw a billiard cue light-end first the least disturbance will cause it spin around to become heavy-end first. Without enough nose weight caravans attempt to do the same are no exception. They must be nose heavy or they’ll attempt the same thing. Excess caravan nose weight, however, levers up the front of the tow vehicle. This reduces the grip of its steered wheels. A further limit to caravan nose weight is that, above 14% (of laden caravan weight), they oppose being pulled in any but a straight line. Or, if they do begin to turn, attempt to keep doing so. This is (to put it mildly) undesirable whilst cornering. It is even more so when needed to swerve to avoid a head on collision.
Caravan nose weight
From the 1930s to 1980 or so caravans were typically 4-5 metres long, weighed 1000-1200 kg, had centre kitchens (and were thus centre-heavy) and rarely towed above 80 km/h. A caravan nose weight of 7%-10% kept most reasonably stable. In the 1980s, however, and particularly in Australia and the USA, the growing acceptance of 4WDs (typically weighing 2-2.5 tonne) enabled makers to sell longer and equally heavy caravans. Many, when laden, well exceeded their tow vehicle’s weight.
Research and practical testing has since showed that a caravan’s weight is less of an issue than its length and, even more, how the weight is distributed. Weight, both in design and loading, needs concentrating close to the axle/s. Ideally, the A-frame should carry no load (e.g, gas bottles, batteries, etc.). Nothing heavy should ever be at the rear. Loading for use should be similar. If your caravan is like this, caravan nose weight of 7%-10% should suffice.
The effect of weight depends on where it is located. Pic: original source unknown.
In recent years, the quest to reduce air pollution entails reducing tow vehicle weight. Such lightening often reduces allowable hitch weight. The UK’s and Europe’s caravan makers develop increasingly lighter caravans. They are now typically 40% less per metre than much local product and have minimal end weight. Some have a recommended caravan nose weight around 5%. Ongoing research however indicates that, for such construction, 6-8% caravan nose weight is better.
In Australia, despite equally lighter towing vehicles, many new caravans remain 6-7 metres long, weigh 2-2.4 tonne unladen and end-heavy. To enable them to be towed by vehicles of often less weight than the caravan’s, some makers recommend caravan nose weight of around 5%. It is legally unwise to do other than suggest buyers follow caravan and tow vehicle makers’ recommendations re tow ball weight. But as such weight is far below that found optimum in test after test, Caravan and Motorhome Books does not necessarily endorse such recommendations. See also the Caravan Council of Australia’s advice – i.e. to have a tow vehicle that, when laden, is about 30% heavier than the laden caravan. http://media.wix.com/ugd/74afe1_64d4b6451dbe4750aa7f32adc777b390.pdf. Also Andrew Woodmansey’s excellent Caravan Buyers Guide http://caravanbuyersguide.com.au/ This issue is also covered in depth in my all new Caravan & Motorhome Book.
For conventional Australian-designed caravans that have a tow vehicle that allows it consider using 8%-12% caravan nose weight. For EU-style caravans (and tow vehicles that allow this), consider using 6%-8% nose weight.
Caravan and Motorhome Books strongly advises to buy a heavy off-road caravan only if intending seriously to drive long distances off-road. Many weigh in excess of 3.5 tonne and have a very high off centre of gravity. Ideally keep interior length to 5-6 metres.It is not feasible to suggest caravan nose weight – except to use as much as the tow vehicle allows – plus (but never engaged off-road) a WDH adjusted to correct only 50% or so of the imposed caravan nose weight. (Using 100% correction of such high mass introduces tow vehicle instability.)
‘You want your money back!?’ – I told you it could be towed by your pick-up truck – I never said you should!‘ Pic: agcoauto
How to ascertain caravan nose weight
Bathroom scales typically weigh up to 185 kg. To weigh more than that (using bathroom scales see: http://hildstrom.com/projects/tonguescale/
(Note: It is technically correct to refer to nose mass (rather than weight) but, for the purposes of this article, the two may be seen as interchangeable.)
For an overall view see also:
Collyn Rivers’ in-depth books cover every aspect of camper trailer, caravan and motor home selection, design, building and use. They include the Camper Trailer Book, Caravan & Motorhome Electrics, Solar That Really Works, and (for homes and properties, Solar Success. Amongst virtually every aspect of caravan and motor home usage, caravan stability is covered in depth in the all new Caravan and Motorhome Book. For information about the author please click on Bio.
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