Caravan weights

The correct definitions are
Tare The dry weight of the van from the factory

GTM the MAXIMUM allowable weight on the axles only.

ATM the maximum allowable loaded weight on axles and jockey wheel

The ballweight is part of the tugs payload.

ATM and GTM are stated limits on a Compliance plate . They are NOT an actual weight at any one time.

That is the ACTUAL LOADED WEIGHT

It IS legal to tow a van with a higher ATM than your vehicles capacity provided at the time it does not weigh more than that capacity.
However who wants so go away with hardly any stuff in it.

I have had this in writing from NSW TMR technical section

Has been a debate raging here

debate on weights

Worth reading the links in there about why a Ute may not be able to tow its maximum tow capacity

You might also bear in mind that the "Tare" mass claimed by the manufacturer may not be, how should I put it, "Accurate"

Exackerly I meant to put that in and forgot

I would stress again that ATM and GTM are not weighable weights.

They are the legal limits that the van can weigh in each circumstance.

The weight on a weighbridge in both instances is the ACTUAL LOADED WEIGHT which may or may not match the above definitions.

EG A van has an ATM on its compliance plate of 3500kg.

You weigh the van loaded it weighs 3465kg That is NOT the ATM it is the actual loaded weight .

The ATM is always what is stamped on the compliance plate and the actual loaded weight should not exceed that.

Admittedly the acronyms are used for what it actually weighs but to be pedantic, that is incorrect.

Further to what has been discussed, I like to go to the source of the legal definitions and use them. You will fing them in "Vehicle Standard (Australian Design Rule – Definitions and Vehicle Categories) 2005." The ones that the OP enquired about are:



If you go to VSB-1 you will find a definition of Tare Mass that applies to trailers alone.

In addition Darian and Tom have introduced a further weight that is needs to be observed

You may note that the definition of GTM here is at odds to the definition that Darian gave. Even the jurnos get it wrong.

True except that tare definition is for a motor vehicle NOT a Caravan.

A caravans Tare should be the weight as it leaves the factory with NO FLUIDS OR GAS

Anything added later comes out of the payload

Here is the best description of the weights I have found so far

http://www.caravancouncil.com.au/#!compliance/c1pna

and click on Ratings and Masses and a PDF will come up

That document of Darians Towing Guide is a bit misguided I reckon

That tare mass definition applies to all vehicles. "Unoccupied and unladen" means no gas, water or diesel in the diesel heater tank. They are part of the load.

Im sorry it doesnt It refers to a motor vehicle which has its radiator and sump full and 10 litres of fuel. As it says quite plainly in the definition if you read it in its entirety

A vans tare is its dry weight with no fluids or gas. To be exact water tanks, empty HWS empty, toilet empty, gas bottles either empty or not even there as in my van that came without them. It only includes what is on it when leaving the factory and if it doesnt have an aircon or an awning then they have to come out of payload.
It would also pay to weigh it yourself as some vans may be well out of wack with whats on the plate.

Jayco say they weigh each individual van. My Roadstar was about 140kg over the plated tare when I bought it

From Caravan World

Tare Mass

Tare mass is the weight of the caravan as it leaves the factory, without water in the tanks, any gas in the cylinders, any luggage or personal effects whatsoever. It is also without the weight of dealer-fitted extras, such as an awning, air conditioner and so on. If you subtract the Tare from the ATM, this leaves you with the maximum payload weight you can use to load your van.

Tom, you can prattle on all you like. When you are dealing with legal things you have to go to the legislation. The definitions in the document that I quoted are the legal definitions used for the things we are talking about. That is the only definition of Tare Mass in the document. The definition includes things only found in powered vehicles because it is the definition for all classes of vehicles. There is no other definition in that document.

There is however another document that is a collection of bits and pieces relevant to trailers, that is VSB-1. The definition of tare mass in that document has been extended to only cover. If you wish to quote another definition you should be quoting that one. Any definition you quote from another source has no force in legislation, it is just a paraphrase or interpretation of the definition defined in legislation.

Alright but here is the definition from VSB1 which is all about trailers and Caravans

12.7 Tare Mass

Tare Mass is the total mass of the trailer when not carrying any load, but when ready for service, unoccupied (if relevant) and with all fluid reservoirs (if fitted) filled to nominal capacity except for fuel, which shall be 10 litres only, and with all standard equipment and any options fitted. This includes any mass imposed onto the drawing vehicle when the combination vehicle is resting on a horizontal supporting plane. (Fluid reservoirs do not include water tanks and waste water tanks fitted to caravans).