Long, oversize and multi-trailer vehicles need warning signs so other drivers know to give them room when overtaking or following. Transport operators, fleet managers and body builders also need clear signs on depots and loading areas. This guide covers the heavy vehicle signs we're asked about most.
Heavy vehicle warning signs are regulated. The Heavy Vehicle National Law (HVNL) and its regulations set when they're needed and their size, colour and placement in most states, and Western Australia sets its own rules through Main Roads WA. Always check the current requirements for your vehicle, permit or notice before fitting signs. This guide is general information.
1. Vehicle warning signs (HVNL states)
These come as split pairs, so they can be fitted either side of the rear doors or across two panels:
- "LONG VEHICLE" split warning sign pair
- "OVERSIZE" split warning sign pair
- "ROAD TRAIN" split warning sign pair
2. Western Australia
WA has its own formats, including pictorial restricted access vehicle (RAV) signs that show the length and shape of the combination:
- WA "OVERSIZE" split warning sign pair
- WA pictorial RAV sign: 25 m truck and dog trailer
- WA pictorial RAV sign: PBS combinations
- WA pictorial RAV sign: road trains and 60 m road train, take care when overtaking
- WA pilot identification door signs for pilot and escort vehicles.
3. Depots, yards and loading areas
- Loading and unloading area for heavy and large vehicles
- Trucks turning and No parking: turning bay
- Heavy vehicle restricted for areas trucks can't enter.
- Light vehicles give way to heavy vehicles
See our loading dock signs guide and private property speed limit guide for more yard signs.
Truck crossing and truck warning signs
Where trucks cross a road, footpath or driveway from a quarry, depot, farm or construction site, a warning sign gives other road users time to slow down. We stock Warning, trucks crossing and the Trucks warning diamond. On public roads, check with your council or state road authority about placement and approvals. For private roads, see our private property road signs guide.
School bus signs
School buses carry their own warning signs. We stock NSW school bus front sign, NSW school bus rear "40 when lights flash" set, QLD school bus front warning sign and QLD school bus warning sign. Check your state transport authority's requirements for your vehicle. For bus stops and depots, see Bus zone with times and arrow and NSW bus entering warning sign.
Material and fitting tips
- Vehicle warning signs see sun, rain, road grime and pressure washers. Aluminium with a reflective finish is the usual choice. See our reflective vs non-reflective guide.
- Check that signs are mounted where the rules require and aren't hidden by loads, doors or equipment.
- Remove or cover warning signs when the vehicle isn't operating as the type the sign describes, if your rules require it.
Frequently asked questions
Do you make signs for a whole fleet?
Yes. Buy 25 or more of the same sign to save an extra 5%, 50+ to save 10%, or 150+ to save 15%, applied automatically. Every sign is made to order and dispatched in 2–3 business days, and shipping is free on orders over $500.
Which sign does my vehicle need?
That depends on the vehicle, its dimensions, its permit or notice, and the state. Check with the NHVR, Main Roads WA or your permit conditions before ordering.
Related: Supplementary plates explained
Looking for something else? Browse every guide in our Sign Guide Library.
