Because knowing your own ball weight is important.
Understanding how ball weight, tow ball weight, caravan ball weight or tow ball mass affects your vehicle and caravan or camper is essential for safe towing. But how do you go about calculating it?
For the technically minded, tow ball mass actually plays a part in a vehicle’s overall payload and needs to be taken into consideration with other masses such as ATM (Aggregate Trailer Mass) and GTM (Gross Trailer Mass).
In simple terms, tow ball weight is actually the force exerted downwards on a vehicle’s tow ball and tow tongue by a caravan, camper or trailer. There’s a few ways to determine tow ball weight, but the general rule of thumb is that it should be around 10% of your fully laden trailer, camper or caravan.
If you know your ATM and your GTM, then ball weight is the difference between the two. An easier option could be to load up your van and drive to the nearest weigh bridge (most local council tips have them these days) and with the trailer axles sitting off the weigh bridge, drop your jockey wheel on, drive your car off and there’s your ball weight.
Then there’s the old bathroom scales and plank trick (look it up), but the simplest, quickest and most effective way is to get yourself a set of ball weight scales.
To test this theory, we got our hands on a set of Towsafe Ball Weight Scales from Mister Hitches.
The compliance plate on the caravan suggested the ball weight of the van was 186kg, so we loaded up, chocked the wheels, set the handbrake, wound the jockey wheel up and placed the trailer scales underneath the hitch where the tow-ball would normally go.
Lowering the jockey wheel, we were pleasantly surprised to see the van sitting down onto the scales at a very close 190kg.
To ensure consistency, we followed the process a few times and with each attempt the scale indicators sat at the same spot.
Remember that exceeding your vehicles maximum ball weight is not only illegal, it’s also very unsafe and can contribute to poor on-road or off-road towing performance of both your van and your vehicle.
For less than $100, why not go in with a few mates and get yourself a ball weight scale and if nothing else, make a point of checking your ball weight soon.