There’s been some interesting arguments online lately, where people are saying that if the nameplate on your trailer states an ATM of higher than what the towing capacity (or BTC; braked towing capacity) is on your 4WD, you can’t tow it.
In essence, if you had a trailer weighing 2500kg, with an ATM of 3100kg and a 4WD with a towing capacity of 3000kg would you legally be able to tow it?
This is the perfect example of the whole weight saga being poorly understood on a consumer level, but also going into those that enforce the rules, and potentially even insurance companies, and its important to know what the laws are, and where you stand should things go wrong.
If you are still unsure of the 7 towing weights that you need to comply with, we wrote a simple towing guide that makes it all very clear. You can read it here – Towing Capacity.
Can your ATM be higher than your towing capacity?
To answer the above question, we need to go back to the definitions of ATM and Towing Capacity, and look at it objectively (and not make assumptions, like so many people do).
ATM stands for Aggregate Trailer Mass, and refers to the maximum weight your trailer can be at any time. It is just a figure, and does not refer to the actual weight of your trailer.
Its essentially the same thing as the GVM or Gross Vehicle Mass of your 4WD. If you exceed the ATM rating, your are overweight and illegal.
Braked Towing Capacity on the other hand, is the maximum weight that your vehicle can legally tow. Of course, when you are looking at weights you need to look at lot further than just ATM and Towing Capacity, but you can see clear as day that ATM and Towing Capacity are not linked together in any way.
Your Towing Capacity refers to the actual, real life weight of the trailer you are towing, and the ATM is the theoretical maximum that you could load your trailer to. In the above example, you most certainly can tow the trailer providing you are under your towing capacity in terms of the actual trailer weight.
The fact that the ATM is higher than your towing capacity is completely irrelevant; its only the actual weight that matters.
I do wonder if people get confused by referring to the total weight of their van as the ATM. The ATM is not what your trailer weighs, but just the maximum that it can legally weigh.
The trick to getting this right is to go through each of the 7 items, and see if you comply with them, and not to mix and match them. If you can answer yes to all of these, you are good to roll.
Does the total weight of your setup come under the maximum GCM of your vehicle?
Does the total weight of your vehicle (including tow ball weight) come in under the GVM?
Does the actual axle weights (front and rear) come under the vehicles maximum axle capacities?
Does the trailer weigh less than the ATM stated on the nameplate?
Does the tow ball weight come under the maximum tow ball weight of your tow vehicle, and the tow bar?
Do you have the right brakes fitted for what you are towing, and are they set up properly?
Is the trailer you are towing lighter than the maximum towing capacity?
But its illegal
Now, I have heard of police officers looking at the nameplates and if its higher than your towing capacity jumping up and down about it, but unless they direct you to a weighbridge and get the actual weights, they have zero leg to stand on.
It would essentially be the same as a police officer pulling you over and saying ‘Mate, I’ve got to give you a fine, because your vehicle has the potential to do 150km/h, and its only 100km/h here’.
Unless you were actually speeding, and they have evidence of it, you cannot be fined for the possibility of speeding, or being overweight.
What about someone driving with a few cartons of beer in the back of the 4WD? Sorry mate, but you’ve got the potential for drink driving, so here’s a fine. Unless you are actually drunk, you have nothing to worry about.
I have heard of caravan manufacturers de-rating the ATM figure to comply with the maximum towing capacity, which is absolutely ludicrous, and if you change your vehicle down the track to something with a higher towing capacity it forces you to go back to the van manufacturer and have it re-rated.
Have you had people tell you that the ATM cannot be higher than your towing capacity? Send them this article!