NATIONAL HEAVY VEHICLE LAW

South Australia Class 3 Truck and Dog Trailer (up to 23m long) Mass and Dimension Exemption Notice 2025 (No.1)

1.        Purpose

This notice exempts certain class 3 truck and dog trailer combinations that are up to 23m long from stated requirements under the Heavy Vehicle (Mass Dimension and Loading) National Regulation (MDL Regulation).

1.        Authorising Provision

1.       This notice is made under the following provision of the Heavy Vehicle National Law (HVNL):

1.       section 117 - Regulator’s power to exempt category of class 1 or 3 heavy vehicles

1.        Title

This notice may be cited as the South Australia Class 3 Truck and Dog Trailer (up to 23m long) Mass and Dimension Exemption Notice 2025 (No.1).

1.        Commencement date

This notice commences on 4 September 2025.

1.        Expiry Date

This notice expires on 3 September 2030.

1.        Definitions

1.       Unless otherwise stated, words and expressions used in this notice have the same meanings as those defined in the HVNL and its regulations:

1.       In this notice: 

Guide means the South Australian Class 3 Truck and Dog (up to 23m long) Mass and Dimension Exemption Notice Operator’s Guide published by the National Heavy Vehicle Regulator, and as amended from time to time.

1.        Application

1.       This notice applies to a class  3 heavy vehicle that meets all the requirements in this section.

1.       This notice applies to heavy vehicle combinations where:

1.       The truck has a single steer axle and a dual-drive tandem  axle group and towing one of the following:

1.             a 3-axle dog trailer; or.
2.             a 4-axle dog trailer; or.
3.             a 5-axle dog trailer.

1.       This notice applies in South Australia.

1.       A heavy vehicle to which this section applies and that complies with the conditions of this notice is an eligible vehicle.

1.        Exemption - Prescribed mass requirements

1.       This notice exempts eligible vehicles from the following mass requirements specified in Schedule 1 of the MDL Regulation:

1.       Section 2 - Mass limits for a single vehicle or combination

1.       The exemptions in this section only apply to the extent provided under the conditional mass limits set out in section 9 of this notice.

1.        Conditions – Total combination mass limits

1.       An eligible vehicle operating under the general mass limits must not be more than for:

1.       If the eligible vehicle is a complying steer axle vehicle, then the steer axle may have an additional mass limit of 0.5t, which is added to the total combination mass limits in section 9(1) of this notice.

1.    Conditions – Axle spacings

1.       An eligible vehicle that is a truck towing a 3-axle dog trailer must comply with minimum axle spacing requirements listed in column 2 in Table 1, as per the spacing reference in column 1 of Table 1.

Table 1: Minimum axle spacings for a truck and 3-axle dog trailer

1.       An eligible vehicle that is a truck towing a 4-axle dog trailer must comply with minimum axle spacing requirements listed in column 2 in Table 2, as per the spacing reference in column 1 of Table 2.

Table 2: Minimum axle spacings for a truck and 4-axle dog trailer

1.       An eligible vehicle that is a truck towing a 5-axle dog trailer must comply with minimum axle spacing requirements listed in column 2 in Table 3, as per the spacing reference in column 1 of Table 3.

Table 3: Minimum axle spacings for a truck and 5-axle dog trailer

1.    Exemption – Prescribed dimension requirements 

1.       An eligible vehicle is exempt from the following dimension requirements under Schedule 6 of the MDL Regulation: 

1.       section 3 – Length (combination or single vehicle)  

1.       An exemption in 1) only applies to the extent that specific conditional dimension limits that are provided in section 12 of this notice. 

1.    Condition – Total combination dimension limit

An eligible vehicle must not be longer than 23.0m in length.

1.    Conditions – Areas and routes

1.       An eligible vehicle complying with the conditions of this notice is authorised to operate on areas and routes stated in this section.

1.       For the purposes of section 119 (1)(a) of the HVNL, an area or route stated in this section is a stated area or route to which this notice applies.

1.       In this notice a reference to a network is a reference to a map or stated route pursuant to section 119(2) of the HVNL.

1.       An eligible vehicle may operate on the Rigid Truck and Dog (23m) (GML) network.

1.       An eligible vehicle can also operate on a network specified in column 1 of Table 4 on the following conditions:

1.       that the vehicle is solely transporting the commodity listed in column 2; and
2.       the vehicle is operating on a road managed by a road manager listed in the Guide.

Table 4: Commodity routes

1.       Regardless of any access granted under this section, an eligible vehicle must comply with any conditions or restrictions applied to a given area or route by the Specified Road Manager Network Requirements in the Guide.

1.       In this section:

network means a map or stated route, including a list or database, presented electronically or otherwise, that represents the stated areas and stated routes authorised under this notice.

1.       An eligible vehicle operating on an area or route specified in this section must comply with any of the following conditions prescribed for that area or route:

1.       Road conditions pursuant to section 160 of the HVNL; and
2.       Travel conditions pursuant to section 161 of the HVNL; and
3.        Vehicle conditions pursuant to section 162 of the HVNL.

Jose Arredondo

Manager Network Access Policy

National Heavy Vehicle Regulator