Know what to do when it's bigger than you

When you're driving on metro or regional roads, you may come across vehicles that are much bigger, wider and slower than you.

Oversize and overmass (OSOM) vehicles and road trains are built to transport very large loads on our roads. At certain times of the year, mainly during seeding and harvest, farmers need to move large agricultural vehicles, so you may also encounter large, slow-moving agricultural vehicles travelling between farms.

It can be daunting sharing the road with these vehicles, but following these simple rules will make your trip a safer one.

How to safely navigate a vehicle that's bigger than you

If you come across an OSOM or large agricultural vehicle, accompanied by a Heavy Vehicle Pilot or Traffic Escort Warden vehicle, please follow these simple steps:

  • Stay alert - you can't always see what's ahead, so it's important you drive to the road conditions
  • Slow down - seeing a Heavy Vehicle Pilot or Traffic Escort Warden vehicle is a warning that there’s something big up ahead
  • Move left - oversize loads and large agricultural vehicles can take up more than half the road or may need to travel in the middle of the road to avoid power lines or other roadside items
  • Prepare to stop and follow directions - Heavy Vehicle Pilots and Traffic Escort Wardens are there to provide directions on how to safely navigate the oversize load

If the OSOM or agricultural vehicle is extra-wide, you may need to pull over completely for the vehicle to pass safely. Take care when re-entering the road – indicate and wait until the entire convoy has passed, including the last Pilot vehicle, where present. 

When following behind an oversize or agricultural vehicle, be patient and keep a safe distance. The driver will sometimes pull over and signal when it is safe for you to pass.

If the rear pilot waves you past or calls you over the UHF radio (using UHF Channel 40) and advises that it’s safe to overtake, proceed with extreme caution. As the driver, you are still responsible for ensuring it is safe to cross the centreline and overtake.



How to safely overtake a vehicle that's longer than you

Road trains can be as long as 12 car lengths, measuring up to 53.5 metres long!

If you come across a road train on a single-lane road and need to overtake, please follow these simple steps: 

  • Be patient. If you can, wait for the next overtaking lane
  • Make sure you have a long, straight stretch of road ahead of you. Overtaking these trucks take a lot longer than a regular truck. If you can’t see what’s ahead, do not overtake and wait for a safer opportunity
  • NEVER overtake on a curve or hill where visibility is reduced
  • Stay out of the vehicles blind spot
  • After you’ve passed, wait until you can see the vehicle’s headlights in your rear-view mirror, and don’t forget to indicate when returning to the left lane.
  • If you’re towing a caravan or trailer, you will need to give yourself extra room.
  • NEVER cut-off an oversize vehicle as they can't stop quickly

Know what to do when it's wider than you



Follow directions

Heavy Vehicle Pilots and Traffic Escort Wardens are there for your safety! They have the same powers as WA Police to direct you around the oversize load. It is important that you stay alert and follow their directions at all times.
Car driving on unsealed road in regional WA

Driving on rural roads

Know the road rules, prepare for the unexpected and plan ahead.

Learn more »
Bigger than you - block.png

Acknowledgement of country

The Government of Western Australia acknowledges the traditional custodians throughout Western Australia and their continuing connection to the land, waters and community. We pay our respects to all members of the Aboriginal communities and their cultures; and to Elders both past and present.

Tell us what you think

Help us improve our website by sharing your thoughts and suggestions.

Provide feedback