Many minor modifications can be carried out without obtaining written approval.
Commonly, minor modifications involve the installation of an accessory (e.g. long range aerial, tow bars, roof racks etc) and provided the vehicle continues to meet the vehicle standards, do not require approval.
Basic modifications are changes to a vehicle that are more significant than a minor modification, but not significant enough to require formal approval from an Approved Person or the Department of Transport and Main Roads.
Complex modifications such as engine upgrades, gearbox and rear axle changes, vehicle body modifications and steering and brake replacements are significant modifications to a vehicle and can seriously affect the safety of a vehicle if not performed properly.
Complex modifications to light vehicles must be certified by approved persons, providing the modifications have been performed in accordance with an approved code of practice.
Some owners require approval for vehicle modifications which may be outside the scope of the approved codes of practice and approval by an Approved Person and must be approved by the department.
Minor modification includes the fitting of optional equipment or alterations to a vehicle within manufacturer’s specifications that do not cause the vehicle to be non-compliant with heavy vehicle standards. Should clarification be required on whether a modification requires approval the NHVR will make a determination.
Examples include; additional lighting, aerials, air conditioning, alarm systems, plastic shields for lamps and windscreens, and manufacturer’s wheel and tyre options (that do not affect the Gross Vehicle Mass (GVM) or Gross Combination Mass (GCM) rating of the vehicle). These modifications do not require approval provided the vehicle continues to be within manufacturer’s specifications and comply with the heavy vehicle standards.
These modifications are those outlined in the NHVR Code of Practice for the Approval of Heavy Vehicle Modifications (PDF, 433KB).
This includes complex modifications that can affect the safety of a vehicle if not performed properly. The modifications included in the Code are based on accepted vehicle engineering practices and the requirements of the heavy vehicle standards. The Code also supplements the recommendations of the original vehicle manufacturer in relation to vehicle modification techniques or standards and provides guidelines where manufacturer’s specifications do not exist.