Tray Truck Load Restraint: What the Rules Require and What to Spec on Your Tray

Key Takeaways

• The forces are set by law: your restraint system must withstand 80% of the load's weight forwards, 50% sideways and rearwards, and 20% upwards when you rely on friction.

• GVM decides which guide applies: up to 4.5t GVM, the NTC's Load Restraint Guide for Light Vehicles 2018. Above that, the Heavy Vehicle National Law, with the NHVR's Load Restraint Guide 2025 as guidance.

• An unrated headboard doesn't count: NHVR guidance treats a headboard or gate with no stated rating or documentation as unrated, and the load as unblocked.

• A rated headboard cuts the restraint you need: if it provides at least 30% of the load's weight in forward restraint, your lashings need to supply 50% rather than the full 80%.

• Spec restraint at order: get headboard, gate and anchor point ratings in writing before the tray is built.

What forces must a tray truck's load restraint withstand?

The loading performance standards are the same for light and heavy vehicles. A restraint system must hold the load against 0.8g forwards, 0.5g sideways and rearwards, and 0.2g upwards if friction is relied on. These are the forces of harsh braking, cornering and acceleration. The NTC also notes that braking forces are typically higher at low speeds, so a slow trip doesn't reduce what you need.

Restraint required for common tray loads, in kilograms of force:

Which load restraint rules apply to your tray truck?

The dividing line is 4.5t GVM.

• Up to 4.5t GVM: laws in Queensland, NSW, Victoria, Tasmania, SA and the ACT refer to the NTC's Load Restraint Guide for Light Vehicles 2018. It says a load must stay on the vehicle through heavy braking, cornering, acceleration and even minor collisions.

• Over 4.5t GVM: the performance standards sit in Schedule 7 of the Heavy Vehicle (Mass, Dimension and Loading) National Regulation. The NHVR's Load Restraint Guide 2025 shows ways to meet them, and the NHVR says the 2018 edition remains valid.

• WA and the NT: both reference the 2004 Load Restraint Guide.

Heavy trucks also bring chain of responsibility duties. Under the Heavy Vehicle National Law, a business that packs, consigns or loads goods for a heavy vehicle must ensure the safety of those activities so far as reasonably practicable.

Why does a rated headboard matter?

Blocking the load against the headboard is often the simplest way to handle the forward force, but only a rated headboard counts. NHVR guidance says that if no rating is stated or documented for a headboard or gate, it is assumed to be unrated and the load is treated as unblocked. A rated headboard is one certified by the manufacturer or a suitably qualified engineer.

The rating changes the maths. Under the NHVR's approach, a headboard that provides at least 30% of the load's weight in forward restraint lets the remaining restraint supply 50%. Below 30%, the headboard is treated as providing no forward restraint, and your lashings must supply the full 80%.

For a 2,000kg load, a headboard rated to at least 600kg leaves 1,000kg of forward restraint for the lashings. Without it, they need 1,600kg.

Position matters too. A load within 200mm of the headboard is generally considered blocked, and the 200mm limit also applies to the total of the gaps along the load. Total sideways gaps should be under 100mm.

What should you specify on a new tray?

Dropside height matters for small rubber-tyred equipment such as mowers. The NTC guide allows it to be contained without vertical tie-down only if the sides and ends are at least 300mm above the deck, higher than the tyres, and limit movement to 200mm front to back and 100mm side to side.

How do lashings and angles change what you need?

Tie-down restraint clamps the load to the deck, so the lashing angle decides how much tension does useful work. The NTC rates a vertical lashing at 100% effective, 60° at 85%, 45° at 70% and 30° at 50%. It puts the minimum effective angle at 35°, so low loads may need packing underneath to raise it.

• Use rated lashings, and never tension them past the manufacturer's lashing capacity.

• Chains suit heavy or unstable loads because they stretch by at most 1% of their length. Webbing straps stretch, so check and re-tension them during the trip.

• Use rope only for light loads, and only if it is rated.

• If an item takes two people to lift onto the truck, tie it down even if it's contained.

• Don't use lifting points on equipment as restraint points. The NHVR says they aren't designed for it.

Questions to ask the tray builder or dealer

1. What is the headboard's rated forward restraint capacity, and can you give me the rating in writing?

2. Are the side gates and tailgate rated, and to what capacity?

3. How many anchor points or rope rail sections are fitted, and what is each one rated to?

4. Is anti-slip matting fitted, or available as an option?

5. How high are the dropsides above the deck?

Compare tray truck quotes with the headboard rating, anchor points and gate specification written into your request. If you mostly carry loose bulk material, a tipper body may suit you better: see Choosing the Right Tipper Body - 2026 Guide.

Frequently Asked Questions

Do I need to tie down a load on a tray with dropsides?

Not always. The NTC says a load can be contained by the vehicle if it's packed snugly and its centre of gravity sits well below the top of the sides. Heavy items may still need tie-down or direct restraint, and anything that takes two people to lift should be tied down.

Does a tarp count as load restraint?

Not on its own. The NTC says most tarps aren't effective restraint and shouldn't be counted when you work out your lashings unless they are rated.

How far can a load stick out the back of a car-licence tray truck?

Under the NTC light vehicle guide, rear overhang measured from the rear axle is limited to 60% of the wheelbase or 3.7m, whichever is less. In WA, the limit is 1.2m behind the vehicle. Outside WA, a rear projection over 1.2m needs a brightly coloured flag by day and a red light visible from 200m at night.