Vehicle modifications

Modified vehicles or individually constructed vehicles may be registered in the Northern Territory (NT) provided they conform to safety standards and are approved by the MVR.

There are different approval processes for different types of vehicle modifications.

You may need to apply for technical advisory committee (TAC) assessment if your vehicle has significant or extensive modifications, or you are building an individually constructed vehicle (ICV).

The TAC meets on the first Wednesday of each month (except January), and the closing date for applications is the close of business on the last Wednesday prior to the scheduled meeting.

There are also requirements for the repair or welding of vehicle components.

To carry out some vehicle modifications you may need engineering certification that is issued by a recognised engineer in the NT.

Modified or individually constructed vehicles (ICVs) may also be subject to periodic inspections at the MVR.

You should check with your insurance company before making any alterations to your vehicle, as some modifications may affect your insurance cover.

If you have built or modified your vehicle, it may have to be assessed by the technical advisory committee (TAC).

The committee provides recommendation to the MVR on the approval and suitability of your vehicle.

It is made up of representatives from various motor vehicle enthusiast groups, transport department officers and NT Police.

Before you start

You will need all of the following:

• a completed application to modify a vehicle PDF (516.9 KB)
• your vehicle details such as the month and year of vehicle manufacture
• additional information that will help in the assessment of your vehicle such as:
  • photos or sketches
  • certification documents such as engineering approval or kit approvals.

How to apply

To apply, submit your application and any supporting documents by mail, email or in person.

You will be notified in writing about the outcome of the assessment.

Vehicle standards officer
Department of Infrastructure, Planning and Logistics
GPO Box 2520
Darwin NT 0801
vehiclestandards.mvr@nt.gov.au 

In person

You can submit your application at an MVR office.

More information

For more information, get the light vehicle modifications information bulletin PDF (921.7 KB).

Light vehicles (up to 4.5t GVM)

The MVR inspectors will assess your vehicle in line with the National Code of Practice for Light Vehicle Construction and Modification, which applies to both the modification of production vehicles and individually constructed vehicles (ICV).

For more information about the code, go to the Australian Government's Department of Infrastructure, Transport, Regional Development and Communications website.

Minor modifications

Minor modifications may be carried out without obtaining approval.

Generally these modifications may include fitment of optional equipment for the vehicle concerned and would not affect the level of safety, strength or reliability of vital systems such as brakes and steering.

Examples include fitting a car audio, bullbar, towbar, additional lighting, manufacturer wheel or tyre options.

Basic modifications

Basic modifications are modifications that do not affect the level of safety, strength and reliability of vehicle systems, and may be assessed and approved at a government inspection facility.

In most cases you don't need to submit a written application or apply to the technical advisory committee.

Some modifications that require certification under the code may also be assessed as a basic modification. Common examples of this can include:

• engine substitution
• fitment of approved child restraint anchorages
• fitment of super/turbo chargers and other engine modifications
• fitment of roll bars/cages
• transmission and rear axle modification and substitution
• motorcycle modifications
• substitute seating
• replacement fuel tanks/cells
• fitment of approved seat belts
• suspension modifications.

Significant modifications and extensive modifications

These modifications include all modifications not classed as a basic modification or a minor modification.

They have the potential to seriously affect the safety of your vehicle and may affect its strength, structural integrity and handling characteristics.

These modifications must be assessed by the technical advisory committee.

In some instances, engineering certification may also be required.

Individually constructed vehicles (ICVs) and street rods

Applications to build an ICV or street rod are assessed by the technical advisory committee.

ICVs will require engineering certification.

For street rods, the technical advisory committee will assess your vehicle according to the National Guidelines for the Construction and Modification of Street Rods in Australia. This includes technical specifications for the construction and modification of street rods.

For more information about the guidelines, go to the Australian Government's Department of Infrastructure, Transport, Regional Development and Communications website.

More information

Read more about light vehicle modifications PDF (921.7 KB).

Some vehicle modifications and some imported vehicles may need engineering certification.

You will have to contact an approved engineer and pay a fee that is set by the private business.

The following table contains engineers who are recognised in the Northern Territory (NT) and may:

• undertake technical assessments
• issue certificates for modifications.

In most cases, the NT will recognise certification provided by an interstate engineer if the engineer is already recognised or approved in their home state or territory by the relevant motor vehicle registration authority.

More information

For more information, read the following:

V79 Northern Territory engineering signatory scheme PDF (708.9 KB)

V83 Recognised engineering signatories PDF (728.7 KB)

You can repair or weld vehicle components as long as you use specialised repair techniques that ensure the protection characteristic and strength of your vehicle is maintained, and not affected by the repair or modification.

Those components can include any of the following:

• chassis
• body structure
• engine mounts
• suspension
• steering shafts
• drive-line components
• towing connections.

Before you start a repair or modification

All welding must be carried out by a qualified welder.

The repairer must use the vehicle manufacturer's recommended repair or welding procedure.

Engineering certification may also be required to confirm that the repairs or modifications have not compromised the vehicle's strength or compliance with vehicle safety standards.

If your vehicle is an older vehicle and doesn't have manufacturer's guide, then any welding or modification must be carried out in accordance with Australian Standards 1554.

Welding of components such as front stub axles, suspension and steering components are not normally recommended. If the manufacturer permits welding on these components, the components may be welded in accordance with the manufacturer's requirements. Non-destructive testing may also be required to ensure the welding is satisfactory. Any tests are the responsibility of the owner.

After a repair or modification

When repairs or approved modifications are completed the welder or their employer must certify in writing that the repairs have been carried out in accordance with the manufacturer's specifications.

You must keep the certification and present it to the MVR during the vehicle's inspection.

More information

For more information get a copy of V31 Repair or welding of vehicle components PDF (431.4 KB)