Legality v Perceived Safety Breach.

Gundog · Guru

Legality v Perceived Safety Breach.

montie · Guru

I have always believed that, in the interest of safe towing, that the tug weight should exceed the van weight by at least 10%.
That is not a legal requirement, just my opinion that in sudden braking situations where you have a 3.5 tonne van on the back of a 2.5 tonne tug the van is likely to take control.

The difference between the "legal" and "perceived" situation?

Your headstone epitaph could read "I was legally right".

The loaded weight of your van unhitched cannot legally exceed to rated towing capacity of the tug.
The loaded weight of your unhitched van cannot legally exceed the plated ATM rating.

Collyn Rivers disagreed with me in the past on another forum stating that the tug should be 30% heavier than the van. I think that might be extreme but again just my opinion.

watsea · Guru

Gundog,
In the survey table, I assumed that GTM of the van actually meant the ATM of the van or the loaded mass of the van.

Gundog · Guru

montie wrote:
The loaded weight of your van unhitched cannot legally exceed to rated towing capacity of the tug.

Montie your statement is conflicting with VSB1 because it says GTM not ATM, also check your vehicles owners manual in my owners manual it states towing capacity is X Kg but it dos not state ATM or GTM, but does state braked trailer with load leveling kit. With that statement is it meaning GTM because unattached the LLK is not in use.

So the point of conjecture is it best to err on the side of caution and use ATM giving you a 10% buffer.

Gundog · Guru

watsea wrote:
Gundog,
In the survey table, I assumed that GTM of the van actually meant the ATM of the van or the loaded mass of the van.

GTM meaning from the caravan compliance plate, it has nothing to do with actual weight

watsea · Guru

Gundog wrote:
watsea wrote:
Gundog,
In the survey table, I assumed that GTM of the van actually meant the ATM of the van or the loaded mass of the van.
GTM meaning from the caravan compliance plate, it has nothing to do with actual weight

On my compliance plate, and I suspect similarly for the many others, there is an ATM and a GTM, with the GTM usually less than the ATM value. That is what I was trying to clarify.

BarneyBDB · Senior Member

For the South Australians this is the current info www.sa.gov.au/topics/driving-and-transport/vehicles/vehicle-standards-and-modifications/loads-and-towing/light-vehicle-towing-regulations

Last week at the Caravan show SAPOL gave me a printed copy that was 4 years out of date and had conflicting info.

Bow · Veteran Member

My vans GTM is 4490kg , you need to adjust the voting card.

Gundog · Guru

Bow wrote:
My vans GTM is 4490kg , you need to adjust the voting card.

Unfortunatly your van is outside the light trailer category, therefore not included in the poll.

Just out of intrest what do you use to tow your van.

montie · Guru

watsea wrote:
Gundog wrote:
watsea wrote:
Gundog,
In the survey table, I assumed that GTM of the van actually meant the ATM of the van or the loaded mass of the van.
GTM meaning from the caravan compliance plate, it has nothing to do with actual weight
On my compliance plate, and I suspect similarly for the many others, there is an ATM and a GTM, with the GTM usually less than the ATM value. That is what I was trying to clarify.

Plated ATM (Aggregate Trailer Mass) is a rating set by the van manufacturer and stamped on the compliance plate. The measured weight of the unhitched van must not legally exceed this rating. An unhitched van includes Ball weight and Axle weights. This the rating that dealers use to determine towing capability.

GTM (Gross Trailer Mass) is defined by VSB as the weight transmitted to the ground via the wheels and tyres and excluding ball weight. There is confusion around plated GTM...is it a rating or a calculation. To arrive at the figure stamped on the plate the manufacturer subtracts the empty ball weight from the ATM so the GTM figure will always be lower than the ATM. IMO it's useless information.

Maximum Towing Capacity is a rating set by the tug manufacturer and is the lesser of the manufacturer rating or towbar rating. Do we use ATM or GTM as the standard. Dealers and manufacturers always use ATM but some will argue that the ball weight is carried by the tug so they use GTM. I think enforcement officers will ask you to unhitch if they suspect your van is overweight so they will be using the ATM to make the determination. If upon weighing your van you are only over by the ball weight you may have that discussion with the nice officer.

GCM (Gross Combination Mass) is a rating set by the tug manufacturer and the combined measured weight of your hitched combination must not legally exceed this rating. Most small SUV's these days seem to have a 6000kg GCM. If you hitch a 3.5tonne van on one of these vehicles it means the maximum your tug can weigh before you hook up is 2150kg. Not a lot of margin for error there. The combination in that case will give you a tug weighing 2500kg and a van weighing 3150kg. I'll leave you to draw your own conclusions.

yobarr · Guru

Bow wrote:
My vans GTM is 4490kg , you need to adjust the voting card.

GTM 4490kg ? I reckon you're referring to ATM, and I could be wrong, but I doubt it. Cheers

yobarr · Guru

I'll bet there's NO van on here with GTM 3500kg. Cheers

yobarr · Guru

Gundog wrote:
We hear in almost every topic about weights and weight distribution, 3.5T is always quoted. But I wonder in fact how many of responders actually have vans weighing 3.5T.
Now we have a bit of a quandary we have a two bob expert and a couple of others who claim the current crop of twin cabs and some SUVs cannot tow 3.5T for whole raft of reasons.
Alas there is nothing in VSB1 that precludes them from doing so, in which most of our caravans fall into the category of a light trailer, a trailer with a GTM not exceeding 3500 kg.
Im almost certain the all those vehicles which manufacturers rate to tow 3500kg, that being the case they would have carried out testing to arrive at that weight, which I assume means GTM, would that mean potentially the ATM could be 3850 kg.
We know that all those vehicles can tow 3500 kg legally, as long as it within the GVM, GCM, GTM, TBW and Axle weights, some will say no you cannot do it safely. One of the drivers of the opinion is the tow vehicle must out weigh the trailer, that an interesting conclusion but quoting various opinions by published authors does not alter it legality to do so.
Some will point to the NVHR regulations about dog and pig trailers must not be heavier than the truck towing them and suggest that it sould apply to our circumstances is pure nonsense.

Graham, you are either very confused, or you have a poor memory, as MANY times I have explained why the car MUST be heavier tgan the van it is towing. Can't soend time to iterate tgat info, as I am driving, but I will get to it some time.

Just because it's "legal" does mean it's "safe". Cheers

P.S 6000kg GCM on the normal twin-cab is La La Land stuff

-- Edited by yobarr on Monday 19th of February 2024 04:55:18 PM

yobarr · Guru

Silly question.Who cares what the GTM is, with the ATM being of most importance, surely?

I seriously doubt that there are any vans around with GTMs of 3500kg.

This is my compliance plate after I increased GTM from 2800kg so that I could fit my Solar system, all my batteries, inverter etc but still carry heaps of water. Cheers

Bow · Veteran Member

Gundog wrote:
Bow wrote:
My vans GTM is 4490kg , you need to adjust the voting card.
Unfortunatly your van is outside the light trailer category, therefore not included in the poll.
Just out of intrest what do you use to tow your van.

Ram 2500. GVM 5700kg

Bow · Veteran Member

yobarr wrote:
Bow wrote:
My vans GTM is 4490kg , you need to adjust the voting card.
GTM 4490kg ? I reckon you're referring to ATM, and I could be wrong, but I doubt it. Cheers

Yes, you are correct

yobarr · Guru

Bow wrote:
Gundog wrote:
Bow wrote:
My vans GTM is 4490kg , you need to adjust the voting card.
Unfortunatly your van is outside the light trailer category, therefore not included in the poll.
Just out of intrest what do you use to tow your van.
Ram 2500. GVM 5700kg

Yay, A REAL Ram, not the Ram 1500 dreamer's wagon. "Tows 4500kg". Yeah, right.

Well done.

-- Edited by yobarr on Tuesday 20th of February 2024 09:40:50 AM

Gundog · Guru

From the number of votes the majority of responders are towing vans 3t and below, so therefore all the popular choices for tow vehicles can actually do the intended job.

This makes me wonder why all the rabbiting on about 3.5t towing capacity causes so much angst.

Alas only 16 votes from over 200 views, are individuals reluctant to vote.

yobarr · Guru

Gundog wrote:
From the number of votes the majority of responders are towing vans 3t and below, so therefore all the popular choices for tow vehicles can actually do the intended job.
This makes me wonder why all the rabbiting on about 3.5t towing capacity causes so much angst.
Alas only 16 votes from over 200 views, are individuals reluctant to vote.

Later!

Are We Lost · Guru

I voted, but it would have been better if you had listed ranges, rather than leave people to choose the closest.

yobarr · Guru

Are We Lost wrote:
I voted, but it would have been better if you had listed ranges, rather than leave people to choose the closest.

Hi Stephen, because I am working long hours I can't devote time to discussing this, but considering that there are, from memory, about 800,000 caravans in Australia the results of a survey in which 19 people participate are hardly relevant?

When I get time, maybe Sunday, I will AGAIN explain to Graham why I regularly use a 3500kg ATM van in my various calculations.

Radar · Guru

Are We Lost wrote:
I voted, but it would have been better if you had listed ranges, rather than leave people to choose the closest.

I thought there was excellent choices.

It would be good if the survey stayed on track , instead of having some bloke coming back with a road train load of puss to confuse things.