I have been reading with much confusion and interest regarding the legality of ball weights, without going deep into the subject could somebody please tell me what my tbw should be on my rig. The car is a 2016 land Rover disco series 4 v6 diesel with a stated ball weight of 350kg as long as my gvm is 200kg less than the max of 3240kg, which it is.
The van is a 2013 23ft Universal with a ATM of 3320kgs. The compliance plate on the van states that the ball weight is 160kgs. This is impossible. the best I can get it down to is 280kg with the van fully loaded and water tanks mt. So at the moment I am running at 9% on the ball. My question is ,,,Am I Legal.
Rodsvan said
03:14 AM May 13, 2025
While it is more common for Aus made caravans to have around 10% TBM, there are some manufacturers who specify anywhere between 5-9%. Has the van had extras such as a toolbox or additional batteries installed up front which could be increasing the ball weight?
Rodsvan said
03:19 AM May 13, 2025
BTW it seems as though Universal caravans are still being made so perhaps you could ask the manufacturer directly.
Silkwood said
11:00 AM May 13, 2025
My understanding (and that's all it is) is that the stated ball weight on the van is the ball weight the manufacturer claims when the van leaves the factory. It has no legal standing. It is your job to ensure all other weights are legal, including maximum ball weight and axle weights for your vehicle. 160kgs does seem a little light on for a 23' van though! I wonder how many weight their vans when they are picked up, and how often the claimed weights are accurate.
As I said, my understanding only, not legal advice!
Cheers,
Mark
freddy fingers said
12:22 PM May 13, 2025
Thanks for your input chaps, I had no idea that Universal vans are still being made, I will chase them up.
cheers, Fred.
Greg 1 said
11:49 AM May 15, 2025
Take no notice of the ball weight listed on your chassis plate.
It is the empty weight without any load at all and is often a wish made in heaven.
It means nothing in any practical sense.
If you aim for a ball weight somewhere around the 10% fully laden you will be OK and legal provided that it is still within the ball load limits of your tow vehicle.
It is much more important to ensure you do not exceed the other critical numbers.
First the vans ATM or maximum loaded weight unattached to the car.
Second the GTM or the weight applied to the vans axle group. This is basically ATM minus ball weight.
Third GVM of the car as fully laden and to include the vans ball weight as the car has that as part of its load.
Fourth the GCM or the overall weight of both car and van combined. This trips up a few people as often this figure is quite low and puts a major limit on what you can tow in any practical sense. That 3500kg tow rating is so much BS.
And finally, often forgotten but equally important, is the cars axle loadings as they can very much be the limiting factor with everything else being within limits but the rear axle load in particular is exceeded.
Once fully laden with full tanks and gas plus all passengers in the car, it is very wise to have the rig properly weighed either at a weighbridge or one of the very good mobile weighing services that have equipment that is even more accurate than most weighbridges. The weighing process involves weighing with the van both hooked up and unhooked so isn't a 5 minute exercise.
Best of luck and may you have many happy adventures out on the road with the rest of us.
Rodsvan said
03:35 AM May 16, 2025
I can't find any govt site which indicates that theTBM specified by the caravan manufacturer is enforceable (however the car/towbar max TBM is enforceable).
I personally would still try and stay within the TBM limits specified by the caravan manufacturer anyway. I would think that they have determined the correct weights for balance and handling of the caravan. They may just pluck some figures out of a hat, but I'd err on the side of caution & also hope that the manufacturer knows their product.
Greg 1 said
04:56 PM May 16, 2025
Rodsvan. The TBW as shown on the chassis plate refers solely to the TBW with the van as it rolls off the production line with no load, no water in the tanks and empty gas bottles.
It has absolutely no bearing whatsoever on the legalities of your van if pulled over on the road for a weigh check.
The only TBW you need to worry about is that specified by both the tow vehicle manufacturer and the manufacturer of the tow bar.
Provided you are within those limitations you are legal.
For arguments sake, my 21' van weighs just on 3 tonne fully laden.
The TBW on the plate is 180kgs but the TBW when laden is 308kgs.
Both my vehicle and towbar are rated to 350kgs TBW so I am well and truly legal and very near to the recommended 10% TBW.
The plated TBW means very little as does the Tare.
Roadside, the weights that they are interested in to ensure you are legal are ATM, GTM, GCM, GVM, axle loads and loaded TBW, nothing else.
Are We Lost said
05:24 PM May 16, 2025
What Greg said.
There may be some exceptions where a maximum towball mass is shown on the plate, but that would be rare. Apart from those rare exceptions, almost every van when laden for travel will have a greater towball mass than what is listed on the plate.
Rodsvan said
04:03 AM May 17, 2025
Duly noted. I was mixing up TBM with maximum tow ball weight.
montie said
01:25 PM May 19, 2025
freddy fingers wrote:
Hi chaps,
I have been reading with much confusion and interest regarding the legality of ball weights, without going deep into the subject could somebody please tell me what my tbw should be on my rig. The car is a 2016 land Rover disco series 4 v6 diesel with a stated ball weight of 350kg as long as my gvm is 200kg less than the max of 3240kg, which it is.
The van is a 2013 23ft Universal with a ATM of 3320kgs. The compliance plate on the van states that the ball weight is 160kgs. This is impossible. the best I can get it down to is 280kg with the van fully loaded and water tanks mt. So at the moment I am running at 9% on the ball. My question is ,,,Am I Legal.
The ball weight stamped on the compliance is the measured dry empty ball weight when the van leaves the factory and is really irrelevant except they use it to calculate GTM.
The recommended ball download should be around 10% of the loaded van which in your case would be be 332kg for a fully loaded van.
Legally your measured ball weight must not exceed the lesser of the following:
1) The tug manufacturers rating
2) The towbar rating
3) The van manufacturer's rating if plated or stated.
Hi chaps,
I have been reading with much confusion and interest regarding the legality of ball weights, without going deep into the subject could somebody please tell me what my tbw should be on my rig. The car is a 2016 land Rover disco series 4 v6 diesel with a stated ball weight of 350kg as long as my gvm is 200kg less than the max of 3240kg, which it is.
The van is a 2013 23ft Universal with a ATM of 3320kgs. The compliance plate on the van states that the ball weight is 160kgs. This is impossible. the best I can get it down to is 280kg with the van fully loaded and water tanks mt. So at the moment I am running at 9% on the ball. My question is ,,,Am I Legal.
As I said, my understanding only, not legal advice!
Cheers,
Mark
Thanks for your input chaps, I had no idea that Universal vans are still being made, I will chase them up.
cheers, Fred.
I personally would still try and stay within the TBM limits specified by the caravan manufacturer anyway. I would think that they have determined the correct weights for balance and handling of the caravan. They may just pluck some figures out of a hat, but I'd err on the side of caution & also hope that the manufacturer knows their product.
There may be some exceptions where a maximum towball mass is shown on the plate, but that would be rare. Apart from those rare exceptions, almost every van when laden for travel will have a greater towball mass than what is listed on the plate.
The ball weight stamped on the compliance is the measured dry empty ball weight when the van leaves the factory and is really irrelevant except they use it to calculate GTM.
The recommended ball download should be around 10% of the loaded van which in your case would be be 332kg for a fully loaded van.
Legally your measured ball weight must not exceed the lesser of the following:
1) The tug manufacturers rating
2) The towbar rating
3) The van manufacturer's rating if plated or stated.
Not many van manufacturers set a ball rating.