Modify a light vehicle: Complex (engineering)

Applicants are required to complete an online application, unless the modification is one that has been gazetted as a modification not requiring formal approval or a modification that can be assessed by an Approved Inspection Station (AIS).

Find out how to obtain any necessary modification approvals.

  Complex: Modifications that require engineering certification and approval

The Department of Transport's (DoT) Vehicle Safety and Standards (VSS) is required to assess applications from people wishing to perform a modification on a vehicle that requires the approval of the Chief Executive Officer (CEO) of the DoT.   

As part of this process applicants are required to complete an online application, unless the modification is one that has been gazetted as a modification not requiring formal approval or a modification that can be assessed by an Approved Inspection Station (AIS)

  Complex: Engineering or modification reports, certificates and certification

Engineering and automotive consultants

The document below provides a list of persons who are recognised by the Department as able to issue engineering or modification reports or certificates for vehicles modified by themselves or under their personal supervision.

  Complex: Stage 1 - Prepare to apply online

Before you can commence any complex vehicle modifications that require approval you must complete a modification application.

DoT's Vehicle Safety and Standards section (VSS) will assess your application and advise you whether you have been granted approval in principle to proceed.

  • Read the guidelines document below before completing the online light vehicle modification form. The guidelines provide you with information in respect to your proposed modifications and refer to the relevant industry bulletins for light vehicle modifications.
  • Please note that you will receive a return email copy of your application once it has been submitted. If you wish to provide photographs or drawings to support your application, please send them via the email address on your response.

Complete the online application form

Complex: Stage 2 - Online application form


  Complex: Stage 3 - Have your online modification application processed

  • Your application will be processed by VSS as soon as possible. However, you should allow a reasonable time for processing.
  • In some cases you may be asked to get engineering certification approval for your proposed modifications.

  Complex: Stage 4 - Once your online application has been assessed and approved in principle

  • Once your application has been assessed and approved in principle by VSS, you will be issued with a letter containing a reference number.
  • Once you have received this approval in principle you can commence to undertake your modifications and an automotive consultant's certification report compiled.
  • Once the automotive consultant's report has been submitted to VSS, the report will be assessed and once approved, you will be issued a written approval.

  Complex: Stage 5 - Complete your modifications and a vehicle inspection

  • Once your modifications have been finalised and a written approval issued, you will need to undertake a vehicle inspection. Please note an inspection fee is payable.

Before you book with AIS to have your modified vehicle inspected, the following must be completed:

  • You must pre-pay for the modification permit before you present the vehicle for inspection.
  • You must present your receipt at the time of the inspection.
  • You must present all documents, engineering certification and approval letter at the time of the inspection.
Pre-pay a vehicle modification permit fee

  Complex: Stage 6 - You are issued with a modification permit

  • If your vehicle passes the inspection and you have paid the required fee, DoT will issue a modification permit to show that your modification has been approved by the CEO of DoT.
  • It is a requirement that you keep these documents inside the vehicle, with copies in a safe place. When your vehicle is sold they must be given to the new owner.
  • It is also recommended that you discuss any modifications you have carried out or intend to make with your insurer, including those listed as modifications not requiring approval. Failure to do this could result in a subsequent insurance claim being denied.

  Applicable legislation and related documents (modify a light vehicle)

Whatever the reason for a modification, the vehicle in question must conform to the following regulations and rules.

  • Australian Design Rules.
  • Road Traffic (Vehicles) Act 2012.
  • Road Traffic (Vehicles) Regulations 2014.

Many minor vehicle modifications can be carried out without our approval. However, they must still comply with the relevant regulations.

Department of Infrastructure, Transport, Regional Development, Communications, and the Arts: Australian Design Rules
Opens in a new window Department of Justice: Road Traffic (Vehicles) Act 2012
Page last updated: Wed May 22 2024 3:18:23 PM