05/06/2026
Big trucks, wide loads, flashing lights - here's what it all means.
A simple guide for caravanners, new drivers and tourists on how to safely meet oversize loads on the road.
(More tips in the comments…)
A Guide to Oversize Loads for Caravanners New Drivers and tourist.
(More tips in the comments...)
Meeting an oversize load coming the other way for the first time can be a gut-dropping moment. Big truck, wide load, pilot cars.
If you haven't got a radio the lights on the pilot indicate the width.
What the lights are telling you
**Standard headlights with amber flashing lights on the roof is a standard oversize. They're generally well within their lane. Ease over to the fog line and keep moving. On most Australian highways you don't need to slow down.
**Standard headlights with roof ambers and white wig-wag lights on the front means the load is over 4.5 metres wide.
It'll often be coming into your lane. Keep an eye on the shoulders of the highway if there's about a metre of shoulder on each side, you can move over onto it and the oversize will usually do the same.
You can usually get past without fully stopping if you move well over and drop your speed. But if there's no shoulder, that's when you have to be careful as there's no extra room to move across.
**If a vehicle with red and blue lights is running behind the first pilot, that's a Traffic Es**rt Warden. Pull completely off the road and stop. What's behind it will be very wide.
**The width numbers you need to understand
If its 4 metres you can generally hold your own lane. Once it goes past four and a half metres they'll be crossing the centre line into yours. Unless there are shoulders on the road.
**On the UHF you'll often hear calls like "4.7 wide, 3.8 at the wheels."
Or if its carrying a dozer you might hear 5 metres 4.3 at the blade.. (not a dozer expert)
The first number is the total load width. The second is how far it'll actually reach into your lane once the truck has moved as far left as it can go.
That second number is the one that matters to you.
So 4.7 meters on a road with shoulders means move over the 70 centimetres will be swallowed by the shoulders if there are no shoulders some of the load will be in your lane.
**Early warning on the UHF
If you have a UHF on, in most cases you can hear an oversize approaching from a long way away. The pilots are usually calling up other trucks well in advance, so having the UHF on gives you a very early warning about the size of the load coming towards you.
Keep the UHF on Channel 40
Pilots will keep it short and sharp. You'll hear things like
"Copy southbound, 5 metres"
"Copy northbound, 3.7 at the wheels"
"Copy caravan, 4.7 wide, can you pull up close to the fog line?"
Or copy westbound we got 2 at 4.7 metres 4.5 at the wheels.
**Overtaking
When a pilot indicates, sticks a hand out the window, or tells you on the radio it's safe to come through, don't hesitate.
They work hard to find safe passing spots and they don't get many. When they give you the green light, take it.
**Bridge closures
You'll hear calls like "Northbound 5 metre oversize approaching. Bridge is closed. Pilot is on the bridge." Or bridge under supervision for a southbound 5 metre oversize.
That bridge is either too narrow or the load too heavy for two vehicles at once. The bridge gets cleared so the load can cross alone, sometimes at reduced speed. When you hear "Clear of the bridge" the oversize has crossed the bridge.
If you hear the bridge call, back off and be ready to stop well before you get there.
**The simple version
UHF on Channel 40 whenever you're on the open road.
When in doubt pull over early and let it through. A few minutes waiting is worth a lot more than a close call.
These loads are moving essential gear around the country. A bit of patience from everyone keeps it moving safely.
Rules can vary a bit between states so if you've got local knowledge or extra tips drop them in the comments and I'll update this post with the best information.
Stay safe.
