Note: This Notice provides an exemption from certain heavy vehicle mass limits outlined in the MDL for eligible Class 3 truck and dog trailer combinations.
This instrument does NOT exempt these heavy vehicles from other requirements of the Heavy Vehicle National Law (HVNL) including other dimension requirements and mass requirements.
The information in this Operator’s Guide is intended to do two things:
Explain how the National Class 3 Truck and Dog Trailer Mass Exemption Notice 2023 (No.1) (the Notice) operates, to assist in complying with it. It is important to remember this Operator’s Guide is instructional only and it is the Notice that provides the exemption or authorisation. If there is a difference or misunderstanding between the Operator’s Guide and the Notice, the Notice has priority and must be followed. The only exceptions are the requirements or conditions set out in the ‘Network and Mapping’ section explained below.
Provide additional information referred to in the network requirements of the Notice. This includes links to network maps and other information such as vehicle, travel and road conditions. Networks and their conditions published in the ‘Network and Mapping’ section of this Operator’s Guide are not general advice and must be treated as conditions of the Notice.
Please read the Notice and this Operator's Guide together. To download or print this guide, use the print or PDF buttons on the top right of this page
Exemptions
These exemptions only apply to the extent to which conditions are granted.
section 2– Mass limits for a single vehicle or combination;
section 5 – Mass limits relating to axle spacing generally.
Note: Other mass and dimension limits in the MDL apply.
Definitions
The following are terms used in this Notice or conditions of operation. Unless otherwise stated, words and expressions used in this Notice have the same meaning as defined in the HVNL.
Means a suspension system certified as a road-friendly suspension system by the Vehicle Safety Standards Branch of the Commonwealth Department of Infrastructure, Transport, Regional Development, Communications and the Arts in accordance with the Vehicle Standards Bulletin Number 11 (revised edition) published by that branch in July 2004.
Complying steer axle vehicle
A complying steer axle is a single steer axle attached to a heavy vehicle that has all of the following —
an engine complying with the emission control requirements contained in—
if a version of ADR 80 later than ADR 80/01 applied to the vehicle at the vehicle’s date of manufacture—the version of ADR 80 that applied to the vehicle at the vehicle’s date of manufacture or a later version of ADR 80;
a front underrun protection device that complies with UN ECE Regulation No. 93 or ADR 84–Front Underrun Impact Protection;
a cabin that complies with UN ECE Regulation No. 29;
appropriately rated tyres, axle and suspension to permit 6.5t on the steer axle;
a GVM of 15t or more.
Dog trailer
Means a trailer (including a trailer consisting of a semitrailer and converter dolly) that has—
one tandem axle group or a single axle at the front that is being steered by connection to a towing vehicle by a drawbar; and
one tandem axle group at the rear.
Drive axle group
Means a tandem axle group or a single axle driven by the vehicle’s engine.
General access
Means access to all roads in participating jurisdictions, except as restricted by the 'Specified road manager network requirements' in the Guide.
Prescribed mass requirement
Means a mass requirement prescribed by the MDL.
Single axle
Means one axle, or two axles in which the horizontal distance between the centre-lines of the outermost axles is less than 1m.
Steer axle
Means the front steerable axle used to steer the vehicle.
Steer axle group
Means a group of one or two axles with single tyres, fitted to a motor vehicle and connected to the same steering mechanism with the axles at least 1m (but not more than 2m) apart.
Tandem axle group
Means a group of at least two axles with the outermost axles at least 1m (but not more than 2m) apart.
Twinsteer axle group
Means a group of two axles with single tyres, fitted to a motor vehicle and connected to the same steering mechanism with the axles at least 1m (but not more than 2m) apart.
Eligible vehicles
This Notice applies to Class 3 rigid truck and dog trailer combinations listed in Table 1.
Configurations that include a tri-axle group are not covered under this Notice.
Table 1: Eligible vehicles
Combination description and diagram
Axle group configuration
Steer axle group
Drive axle group
Trailer front axle group
Trailer rear axle group
3-axle rigid truck towing a 3-axle dog trailer
Single
Tandem
Single
Tandem
4-axle rigid truck towing a 3-axle dog trailer
Tandem
Tandem
Single
Tandem
3-axle rigid truck towing a 4-axle dog trailer
Single
Tandem
Tandem
Tandem
4-axle rigid truck towing a 4-axle dog trailer
Tandem
Tandem
Tandem
Tandem
Conditions
Notices are subject to various conditions to ensure public safety, protect road infrastructure and prevent adverse impacts on the community, such as noise, emissions and traffic congestion. See the sections below for specific conditions related to this Notice.
Dimension conditions - Click to expand
Under this Notice an eligible vehicle must:
not exceed 19m in overall length; and,
comply with the dimension conditions listed in this section for the relevant combination.
3-axle rigid truck and 3-axle dog trailer
Eligible 3-axle rigid truck and 3-axle dog trailer combinations must comply with the dimension requirements outlined in Figure 1.
Figure 1: 3-axle rigid truck and 3-axle dog trailer dimension diagram
Australian Capital Territory conditions
Eligible 3-axle dog trailers are restricted to a maximum trailer height of 3.5m. Trailer height includes both the trailer and the trailer load.
New South Wales conditions
Eligible 3-axle rigid truck and 3-axle dog trailer combinations operating in New South Wales must comply with the following dimension requirements:
dog trailer height (including trailer and trailer load) is restricted to 3.5m; and,
dog trailer extreme axle spacing must be at least 4.3m.
Queensland conditions
Eligible 3-axle rigid truck and 3-axle dog trailer combinations operating in Queensland must comply with the following dimension requirements:
dog trailer extreme axle spacing must be at least 3.8m.
South Australia conditions
Eligible vehicles operating in South Australia must comply with the additional dimension requirements outlined in Table 2.
Measurements for the distance between two specified axles are taken from the centre of the first axle to the centre of the second axle.
Table 2: 3-axle rigid truck and 3-axle dog trailer South Australia dimension requirements
Axle 1-4
Axle 1-6
Axle 2-4
Axle 2-6
Dog trailer extreme axle spacing
Drawbar length
At least 6.3m
At least 12.5m
At least 4.3m
At least 8.8m
At least 3.8m
Between 3.0m and 5.0m
Victoria conditions
Eligible 3-axle rigid truck and 3-axle dog trailer combinations operating in Victoria must comply with the following dimension requirements:
rigid truck wheelbase must be at least 4.3m; and,
dog trailer extreme axle spacing must be at least 3.8m.
4-axle rigid truck and 3-axle dog trailer
Eligible 4-axle rigid truck and 3-axle dog trailer combinations must comply with the dimension requirements outlined in Figure 2.
Figure 2: 4-axle rigid truck and 3-axle dog trailer dimension diagram
Australian Capital Territory conditions
Eligible 3-axle dog trailers are restricted to a maximum trailer height of 3.5m. Trailer height includes both the trailer and the trailer load.
New South Wales conditions
Eligible 4-axle rigid truck and 3-axle dog trailer combinations operating in New South Wales must comply with the following dimension requirements:
dog trailer height (including trailer and trailer load) is restricted to 3.5m; and,
dog trailer extreme axle spacing must be at least 4.3m.
Queensland conditions
Eligible 4-axle rigid truck and 3-axle dog trailer combinations operating in Queensland must comply with the following dimension requirements:
dog trailer extreme axle spacing must be at least 3.8m.
South Australia conditions
Eligible vehicles operating in South Australia must comply with the additional dimension requirements outlined in Table 3.
Measurements for the distance between two specified axles are taken from the centre of the first axle to the centre of the second axle.
Table 3: 4-axle rigid truck and 3-axle dog trailer South Australia dimension requirements
Axle 1- 4
Axle 1-5
Axle 1-7
Axle 3-5
Axle 3-7
Dog trailer extreme axle spacing
Drawbar length
At least 5.0m
At least 8.0m
At least 12.5m
At least 4.3m
At least 8.8m
At least 3.8m
Between 3.0m and 5.0m
Victoria conditions
Eligible 4-axle rigid truck and 3-axle dog trailer combinations operating in Victoria must comply with the following dimension requirements:
rigid truck wheelbase must be at least 4.3m; and,
dog trailer extreme axle spacing must be at least 3.8m.
3-axle rigid truck and 4-axle dog trailer
Eligible 3-axle rigid truck and 4-axle dog trailer combinations must comply with the dimension requirements outlined in Figure 3.
Figure 3: 3-axle rigid truck and 4-axle dog trailer dimension diagramSouth Australia conditions
Eligible vehicles operating in South Australia must comply with the additional dimension requirements outlined in Table 4.
Measurements for the distance between two specified axles are taken from the centre of the first axle to the centre of the second axle.
Table 4: 3-axle rigid truck and 4-axle dog trailer South Australia dimension requirements
Axle 1-5
Axle 1-7
Axle 2-5
Axle 2-7
Dog trailer extreme axle spacing
Drawbar length
At least 7.9m
At least 17.5m*
At least 6.0m
At least 11.0m
At least 5.0m
Between 3.0m and 5.0m
*Note: The gross mass of the combination is reduced by 0.5t for each 0.5 metres reduction in extreme axle spacing (axle 1-7)
Victoria conditions
Eligible 3-axle rigid truck and 4-axle dog trailer combinations operating in Victoria must comply with the following dimension requirements:
rigid truck wheelbase at least 4.5m and dog trailer wheelbase at least 5.0m; or,
rigid truck wheelbase at least 4.9m and dog trailer wheelbase at least 5.5m.
4-axle rigid truck and 4-axle dog trailer
Eligible 4-axle rigid truck and 4-axle dog trailer combinations must comply with the dimension requirements outlined in Figure 4.
Figure 4: 4-axle rigid truck and 4-axle dog trailer dimension diagram
South Australia conditions
Eligible vehicles operating in South Australia must comply with the additional dimension requirements outlined in Table 5.
Measurements for the distance between two specified axles are taken from the centre of the first axle to the centre of the second axle.
Table 5: 4-axle rigid truck and 4-axle dog trailer South Australia dimension requirements
Axle 1- 4
Axle 1-6
Axle 1-8
Axle 3-6
Axle 3-8
Dog trailer extreme axle spacing
Drawbar length
At least 5.0m
At least 9.7m
At least 17.5m*
At least 6.0m
At least 11.5m
At least 5.0m
Between 3.0m and 5.0m
*Note: The gross mass of the combination is reduced by 0.5t for each 0.5 metres reduction in extreme axle spacing (axle 1-8)
Victoria conditions
Eligible 4-axle rigid truck and 4-axle dog trailer combinations operating in Victoria must comply with the following dimension requirements:
rigid truck wheelbase at least 4.5m and dog trailer wheelbase at least 5.0m; or,
rigid truck wheelbase at least 4.9m and dog trailer wheelbase at least 5.5m.
Mass conditions - Click to expand
Eligible combinations must comply with the mass limits and conditions outlined in this section.
Additional or conditional mass allowed under this notice must not exceed manufacturer mass limits pursuant to section 8 of the MDLs.
Note: Dog trailer mass limits may result in an overall mass that is lower than the specified combination mass limit. Where two mass limits are possible for an eligible combination, the lower mass limit applies, and the higher mass limit must be disregarded.
3-axle rigid truck and 3-axle dog trailer
Refer to Table 6 for mass limits and conditions that apply to 3-axle rigid truck and 3-axle dog trailer combinations.
Table 6: 3-axle rigid truck and 3-axle dog trailer mass limits and conditions
Mass limit
ACT
NSW
QLD
SA
VIC
Total combination mass limit
Up to 48.0t
Up to 48.0t
Up to 45.0t
Up to 45.0t
Up to 45.0t
Dog trailer mass limit
Must not exceed rigid truck mass by more than 25%
Must not exceed rigid truck mass by more than 25%
-
Up to 22.5t
Up to 22.5t
Additional allowance
An additional 0.5t can be added to the total combination mass limit for eligible vehicles with a complying steer axle.
4-axle rigid truck and 3-axle dog trailer
Refer to Table 7 for mass limits and conditions that apply to 4-axle rigid truck and 3-axle dog trailer combinations.
Table 7: 4-axle rigid truck and 3-axle dog trailer mass limits and conditions
Mass limit
ACT
NSW
QLD
SA
VIC
Total combination mass limit
Up to 50.0t
Up to 50.0t
Up to 45.0t
Up to 45.0t
Up to 45.0t
Dog trailer mass limit
Must not exceed rigid truck mass by more than 25%
Must not exceed rigid truck mass by more than 25%
-
Up to 22.5t
Up to 22.5t
Additional allowance
An additional 0.5t can be added to the total combination mass limit for eligible vehicles with a complying steer axle.
3 or 4-axle rigid truck and 4-axle dog trailer
Refer to Table 8 for mass limits and conditions that apply to 3 or 4-axle rigid truck and 4-axle dog trailer combinations.
Table 8: 3 or 4-axle rigid truck and 4-axle dog trailer mass limits and conditions
Mass limit
ACT
NSW
QLD
SA
VIC
Total combination mass limit
Up to 50.0t
Up to 50.0t
Up to 50.0t
Up to 50.0t
Up to 50.0t
Dog trailer mass limit
Must not exceed rigid truck mass by more than 25%
Must not exceed rigid truck mass by more than 25%
Must not exceed rigid truck mass by more than 25%
Must not exceed the lesser of:
up to 27.5t
25% greater than rigid truck mass
Additional allowance
An additional 0.5t can be added to the total combination mass limit for eligible vehicles with a complying steer axle.
Axle spacing mass limits
Where the combination is more than 42.5t, it must not be more than the mass limit stated in:
Table 9 below, where the length of the axle spacing is 14m or more.
Table 9: Extension of axle spacing mass limits general table for axle spacings at or exceeding 14m
Length of axle spacing (m)
Maximum combination mass limit (t)
At least
Less than
14.0
14.5
46.5
14.5
15.0
47.0
15.0
15.5
47.5
15.5
16.0
48.0
16.0
16.5
48.5
16.5
17.0
49.0
17.0
17.5
49.5
17.5
–
50.0
General conditions - Click to expand
Suspension requirements
The drive axle group of the truck and all axles of the dog trailer must be fitted with:
air suspension with effective dampers; or
certified road friendly suspension.
Certified Road-Friendly Suspension (RFS)
Single axles or axle groups loaded at the increased mass limit must be fitted with a certified RFS system. RFS reduces the impact of laden axles on road pavements and most bridge structures.
Any axle or axle group not loaded to mass limits greater than GML does not need to be fitted with an RFS system.
A single axle or axle group must qualify for the stated GML and be fitted with the certified RFS before increasing to the stated increased mass limit.
Before an eligible vehicle is driven along any route, its driver and operator must be satisfied that the route has been assessed and that the vehicle can be driven along it without:
disrupting telecommunication, electricity, rail, gas, water or sewage services; or
damaging a road (including a bridge), structure, rail crossing or tree.
Third party approvals
Gazette notices, permits and some jurisdictional laws may require third parties and other entities to provide permission for a vehicle to travel if it exceeds certain mass or dimension limits.
Operators must secure all approvals from third parties such as electricity/utility companies, rail authorities and other third parties as part of their heavy vehicle operations.
Under the HVNL, every party in the Chain of Responsibility (CoR) has a positive duty to ensure the safety of their activities in relation to a heavy vehicle. This duty, known as the “primary duty”, applies to the scheduling, loading and consigning of a vehicle, as well as to its operation on a road.
Safety is broader than the safety of drivers and other road users. It also includes protection of road infrastructure, preventing damage to other vehicles or property, and minimising environmental harm. Substantial penalties may be imposed upon parties who breach this obligation and upon their executives.
For more information on your CoR obligations visit Chain of Responsibility on the NHVR website.
Our Regulatory Advice offers guidance, tips and tools for managing a range of heavy vehicle safety risks.
The requirement to carry the Notice
Drivers do not need to carry a copy of the Notice.
Network and mapping
For the purposes of s121 of the HVNL, an area or route specified in the 'Network & Mapping' section of this Operator's Guide is a stated area or route to which this Notice applies. In addition to complying with the conditions stated in this Operator's Guide, operators must ensure compliance with the specific road manager access requirements set out below or in network maps.
National Network Map
This Notice may refer to state or territory government websites for the publication of networks. From 20 December 2023, certain authorised heavy vehicle road network maps for the Australian Capital Territory, New South Wales, Queensland, South Australia, and Victoria are published by the National Heavy Vehicle Regulator, through the NHVR National Network Map. Additional information and guidance can be found on the National Network Map webpage.
Approved routes covered by the Notice
The following routes are approved for travel for vehicles eligible under this Notice.
New South Wales, Queensland, South Australia, and Victoria
Eligible vehicles have access to all roads in New South Wales, Queensland, South Australia, and Victoria, except as noted in the 'Specified road manager network requirements' section.
This network is maintained through the NHVR National Network Map. Information and guidance on how to use the maps can be found at National Network Map.
Specified road manager network requirements
The following section outlines specific road manager network requirements under the Notice, including route conditions, restrictions, and non-participating road managers.
Road manager network requirements in this section may change from time to time and should be reviewed regularly to ensure compliance.
For further information on how to comply with a requirement, please contact the relevant road manager.
Road managers may publish specific route conditions and restrictions on the approved network map. These must be complied with in addition to any route requirements outlined in this Operator's Guide. If a condition listed in any section of this Operator's Guide conflicts with a route condition or restriction published on an approved network map, the more restrictive requirement applies.
3-axle rigid trucks towing 3-axle dog trailers (6 axles total) are not permitted to operate on the restricted structures listed in Table 10.
Table 10: Restricted structures in South Australia
Restricted vehicle
Restricted structure
Restricted structure location
3-axle rigid trucks towing 3-axle dog trailers
Gumeracha Bridge
Over River Torrens on Torrens Valley Road between Chain of Ponds and Gumeracha
Railway Tunnel (Murray Bridge)
Under Bridge Street, Murray Bridge
Old Murray Bridge
Bridge Street, over the River Murray at Murray Bridge
Birkenhead Bridge
Nelson Street, over Port River at Port Adelaide (the lifting bridge)
Railway Bridge at Gawler
On Overway Bridge Road, Gawler
Traffic advisory services - Click to expand
Prior to commencing any journey, operators should review traffic alerts, road closures, travel delays, and other traffic advisory information for participating jurisdictions.
Table 11 provides details and links to official traffic advisory services for each participating jurisdiction. For more information about a particular service, contact the relevant jurisdiction or department via the contact details listed on the service webpage.
View live information about incidents and changes in South Australia traffic conditions.
Traffic SA is available as a mobile app. See Addinsight download details on the Traffic SA website.
View live information about incidents and changes in Victoria traffic conditions.
Applying for a permit - Click to expand
Access permit applications are required for heavy vehicles that don’t comply with the conditions set out in a notice and when accessing routes that aren’t covered on an approved network.
The following pages provide useful information and resources for submitting access permit applications:
Do I need a permit?: Information and resources for determining whether a road access permit, or a Notice is required to operate on Australian roads.
In this tab, you will find a list of national, state and territory notices related to the National Class 3 Truck and Dog Trailer Mass Exemption Notice 2023 (No.1).
A related notice may be comparable with this Notice or provide alternatives for operators to find the appropriate notice under which to operate.
Authorises the use of 3 and 4 axle trucks towing 3-, 4-, or 5-axle dog trailer PBS combinations on gazetted networks. This Notice refers to other documents that may also be required to be carried including other notices, certificates, codes of practice, maps etc.
Please note the following supporting documents for this Notice:
Provides 3-axle truck and 4-axle dog combinations that do not exceed 20m in length with access to approved networks in the ACT, New South Wales, Queensland, South Australia and Victoria.
Please note the following supporting documents for this Notice:
Exempts truck and dog combinations that are longer than 19m but no longer than 31.5m from the steer mass limits and dimension requirements including length, width and height of the Heavy Vehicle (Mass, Dimension and Loading) National Regulation.
Provides exemptions to dimension requirements for a Class 3 heavy vehicle consisting of a rigid truck and a dog trailer that is transporting Stobie poles.
Concession for log-carrying truck and dog trailer combinations to be up to 22m long.
Resources
There are currently no resources, supporting documents, tools, or calculators for this Notice. All information about these Notices is contained in this Operator’s Guide. Please refer to the tabs for more information about these Notices, or contact us with your specific questions.
Note: If you have any feedback on the information provided, please contact us at info@nhvr.gov.au
Participating jurisdiction heavy vehicle resources
For more information about operating a heavy vehicle in participating jurisdictions, refer to the following sites:
Amended 'Table 2: 3-axle rigid truck and 3-axle dog trailer South Australia dimension requirements' to correct the dimension requirements and axles for a 3-axle rigid truck and 3-axle dog trailer.
22 November 2023
National Class 3 Truck and Dog Trailer Mass Exemption Notice 2023 (No.1) commenced.
Road managers
Accessibility tools
