Dimension Limits

In Recent Years The Consequences Of Not Complying With The Legal Dimension Limits For Heavy Vehicles Have Been Spectacularly Displayed With New South Wales’ Major Roads Being Blocked By Trucks Whose Drivers Have Found Themselves Stuck In Bridges And Tunnels. As A Result, The Authorities Have Stepped Up Enforcement Of The Strict Dimension Limits Set By The Law.

This section discusses the dimension requirements, and the consequences of breaching them.

What Are The Dimension Limits?

Generally vehicles must not exceed the following dimensions:

For a vehicle towing one trailer there is a limitation on the length allowed from the point of articulation to:

Height 4.3 metres
For a single vehicle: 12.5 metres
For a b double: 25 metres
For a road train: 53.5 metres
  • the “rear overhang line”; and
  • the rear of the vehicle.

The distance from the point of articulation cannot be more than 9.5 metres from the rear overhang line, and 12.3 metres from the rear of the trailer.

Width 2.5 metres

The above limits are general limits only. There are a number of exceptions, and other special limits applying to heavy vehicles. These include special limits for the overall size of vehicles, and additional limits on the distances between certain components of vehicles.

Due to the complexity of determining all of the limits applying to any vehicle, it is important that participants in the trucking industry have a good understanding of the law. If you would like assistance in determining the limits applying to your vehicle, please contact us to speak with one of our experienced traffic lawyers.

What If Someone Else Was Operating The Vehicle At The Time?

Where a dimension breach is detected, the RMS (RTA) can charge any of the people in the chain of responsibility for the offence. In practice the RMS (RTA) often seeks to prosecute the operator of the vehicle. It does this by issuing the Court Attendance Notice to the person in whose name the vehicle is registered, i.e. the “registered operator”.

Just because a person is the registered operator of the vehicle, does not mean that person was operating the vehicle for the purposes of the offence. The law says that the operator of a vehicle is the person responsible for controlling or directing the operations of the vehicle. It is usually the person or company running the business in which the truck is used.

The registered operator may not have the necessary control of the vehicle to be classified as the actual operator, for example, if it has been leased to another business.

If you were the registered operator, but not the actual operator of the vehicle, at the time of the offence you must provide a statutory declaration to the RMS (RTA) nominating the actual operator within 14 days of receiving the Penalty Notice or Court Attendance Notice. If you do not do this, the law provides that you are “taken to be guilty” of the offence.

The information which must be contained in the statutory declaration is strictly prescribed by law. If you do not provide a complying statutory declaration in time the court can find you guilty of the overload offence, and punish you as if you were the actual operator.

If you believe that you were not the operator of the vehicle at the time of an offence for which you have been charged, you can contact one of our experienced traffic lawyers on (02) 9261 4555.

The Reasonable Steps Defence

A “reasonable steps defence” is available to defendants charged with a dimension breach offences if the person:

  • is the consignor
  • is the packer
  • is the loader
  • is the operator and the offence is a minor risk breach
  • is the driver and the offence is a minor risk breach

To succeed in this defence you must satisfy the Court that:

  • you did not know, and could not reasonably have been expected to have known, of the dimension breach; and
  • either:
    • you took all reasonable steps to prevent the contravention; or
    • there were no steps that you could reasonably be expected to have taken to prevent the contravention.

Although this defence seems straight forward, it is in practice quite technical to prove. If you think that you may have a reasonable steps defence to your overload charge, you can contact one of our traffic lawyers on (02) 9261 4555.


In NSW, traffic offences are treated seriously. Therefore, it is important to get competent legal advice as early as possible, whether you have received a penalty notice, had your licence suspended or been charged with a serious offence. Our lawyers are highly experienced and understand the difficulties you face without a licence. We can guide you through the process while dealing with the various authorities related to your matter.


Armstrong Legal
Social Rating
Based on 295 reviews
Legal Hotline.
Open 7am - Midnight, 7 Days
Call 1300 038 223