Understanding ATM, Tare and Payload

When buying a plant trailer, there are three numbers you really need to understand: ATM, tare and payload.

They might sound like something you need a calculator, a degree and a quiet afternoon to understand. Thankfully, they’re actually pretty simple – and getting them right is important when choosing a trailer for your excavator, skid steer or other machinery.

What is Trailer Tare Weight?

Tare weight is essentially what your trailer weighs when it’s empty.

So, if your plant trailer weighs 1,000kg before you load your excavator, buckets, tools and equipment onto it, its tare weight is 1,000kg.

It matters because the trailer itself forms part of the total weight you’ll be towing.

What does ATM mean?

ATM stands for Aggregate Trailer Mass.

This is the maximum permitted total mass of the trailer when fully loaded and not connected to the towing vehicle. It includes the weight of the trailer itself plus the load it’s carrying.

For example, imagine your trailer has:

• ATM: 4,500kg
• Tare: 1,000kg

That leaves a theoretical maximum payload of 3,500kg.

And payload is where things get interesting.

What Is Trailer Payload?

Payload is how much weight your trailer can actually carry.

When choosing an excavator trailer or plant trailer, don’t look at the excavator alone. You also need to account for everything traveling with it.

That could include additional buckets, augers, hydraulic breakers, tools and other equipment.

A 3,000kg excavator plus 400kg of attachments is a 3,400kg load. Those attachments don’t become magically weightless just because they’re sitting beside the excavator.

Why do these numbers matter?

Understanding ATM, tare and payload helps you choose a trailer that’s suitable for the machinery you actually transport.

You also need to make sure your towing vehicle, towbar, coupling, axles and other relevant components are appropriately rated for the combination.

Importantly, don’t assume a trailer advertised as a “3.5 tonne trailer“ can carry 3.5 tonnes of machinery. The trailer’s own weight needs to be taken into account.

Choosing the right Plant Trailer

At Alltrades Trailers, we build trailers around real-world working requirements.

If you’re unsure what size plant trailer you need, tell us your excavator or machinery make and model, the attachments you normally carry and what vehicle you’ll be towing with.

We’ll help you work out a trailer specification that makes sense – because when you’re towing several tonnes of machinery, “she’ll be right” isn’t really a specification.

It’s what we do all day, every day, so give us a yell on 1300 611 301 or use the form below and we’ll get you sorted.