Millions of dollars are spent every year on repairing signage, bridges and tunnels due to trucks striking them. The maximum height for a vehicle is 4.3m unless it is a cattle crate or car transporter, which must not exceed 4.6m.
Signs are posted prior to sections of road with low clearance, such as a low bridge, an overpass or a tunnel. Warning lights might also flash if an overheight load is approaching. Drivers must always obey these because if they hit an obstacle due to the load being overheight, the fines are substantial.
How much are the fines?
An on-the-spot fine of $4097 is applicable in New South Wales with a maximum fine of $5500. The driver may also receive a 6-month suspension for both the driver licence and the truck registration, and demerit points.
How can drivers avoid an overheight load?
As a driver’s load is unloaded, the suspension will decompress due to less weight. This can cause an increase in height that’s enough to raise a load that is borderline to be overheight.
Drivers who don’t load their own truck or trailer are still responsible for the dimensions. If a driver is unsure whether the load is overheight, a tape measure will verify it.
If a driver is legally driving overheight (e.g. has the correct permit), then signs warning of overheight assets must be obeyed and the driver must take an alternative route. Signs are usually placed far enough in advance for the driver to pull off the road and find another way.
A load might move, changing the height. Drivers should check a load after a few kilometers.
Digger booms are a very common cause of overheight loads. When loading a large digger, follow the manufacturer’s instructions for storing the boom.
Drivers should ensure that tipper bodies and other attachments are lowered before driving.
Drivers can use low loader trailers for tall loads.
Drivers should ensure that their suspension and turntable heights are set correctly.
Darren is an expert on driving and transport, and is a member of the Institute of Advanced Motorists
