Owning and using a caravan requires you to have at least a little technical know-how, especially when it comes to safety parameters. If you’ve just purchased your first caravan, the plethora of technical terms and prerequisites can get rather overwhelming. The term ‘caravan ball weight’ (or ‘tongue weight’ / ‘tow ball weight’) is probably something you’ve been coming across frequently. So what is it exactly, and how (and why) should you be measuring it?
Understanding your caravan’s ball weight
The tow ball serves as the tool with your caravan can be hitched to your towing vehicle. This tool is affixed to the chassis of the towing vehicle, and accepts a towing hitch which is attached to the caravan. Now, the tow ball would need to accommodate the specific size (and weight) of your loaded caravan. Which is why your caravan’s ball weight is directly dependent on the weight of the caravan loaded at full capacity. This includes the tare weight (weight of the body of the caravan alone), plus its payload (furniture, accessories, equipment, and anything else that you’re carrying in it). As a thumb rule, your caravan’s ball weight is about 8-10% of this total weight.
Measuring your caravan’s ball weight
There are multiple ways of measuring your caravan’s ball weight. You can take your caravan to a weighbridge to have it professionally measured, or just use regular bathroom scales. If you’re choosing the latter, you can also consider buying a dedicated ball weight measuring scale to get more accurate readings.
Using a bathroom scale:
To use a regular bathroom scale for determining your caravan’s ball weight, you will need the following accessories:
- A brick (or paver)
- Two small lengths of pipe (15-20cm each will suffice)
- A sturdy wooden plank (1-1.5m long)
Place the scales and the brick on level ground, about 90cm apart. Place a length of pipe on each, and run the wooden plank across like a bridge. Now place the jockey wheel of your fully loaded caravan on this plank, at about 2/3rd the length from the weighing scale. Record the reading on the scale, and multiply it by 3 to get your caravan’s approximate ball weight.
Using a ball weight measuring scale:
A ball weight measuring scale is much easier to use, and gives a much more accurate reading. This scale typically consists of a calibrated metal cylinder with a heavy base and an internal spring mechanism. All you would need to do is to fix it to your caravan (just like you couple your towing vehicle to it), and the scale will adjust itself to return the caravan’s ball weight reading.
Your caravan’s ball weight should always be less than the towbar weight listed in your towing vehicle’s manual. Failing this, the rear axle of your towing vehicle can be pushed too far down once the caravan is hitched. This will in turn lift up the front axle and severely compromise the performance of your towing vehicle. In order to retain control over braking and steering on rough roads, check your caravan’s ball weight carefully and ensure that you do not overload your caravan. At the same time, it is also important to understand that a certain minimum weight will be required in order to prevent your caravan from swaying excessively. A weight distribution hitch takes care of both situations and is a good way to manage the caravan’s weight better.
Stay safe and negotiate the outback with finesse!