You may need this approval to modify a heavy vehicle that has a gross vehicle mass (GVM) or an aggregate trailer mass (ATM) of more than 4.5 tonnes.
Approval is required for common modifications under the Code of Practice for the Approval of National Heavy Vehicle Modifications. It is also required for complex modifications that are outside this code and may cause the vehicle to be non-compliant with relevant standards.
Approval is not required for simple modifications, including:
- additional ADR-compliant lighting
- aerials
- air conditioning
- alarm systems
- plastic shields for lamps and windscreens
- manufacturer's wheel and tyre options (that do not affect the GVM or gross combination mass (GCM) rating of the vehicle).