Heavy vehicles (any vehicles with a gross vehicles mass over 3,500 kg) including trucks, larger trailers, motor homes and buses, legally require inspection and a Certificate of Fitness (CoF) every six months to ensure the vehicle meets required safety standards (See NZTA to find the standards that apply to your vehicle).
Inspections for Certificates of Fitness for heavy vehicles are conducted at NZTA approved testing stations such as the Automobile Association (AA), Vehicle Inspection New Zealand (VINZ) or Vehicle Testing New Zealand (VTNZ).
If, as a result of an inspection you need to have some repairs or alterations done, or the testing agent requires certification for some aspect of the vehicle, or you are planning on designing a new component or modifying your vehicle in some way, you need to contact a Heavy Vehicle Certifying Engineer (HVCE).
NB: Most light vehicles require Warrants of Fitness (WoF) every six months. If your vehicle requires a WoF and you need to have some repairs or alterations done, or the testing agent requires certification for some aspect of the vehicle, you need to contact a Light Vehicle Certifier. Modifications are certified by a Low Volume Vehicle Certifier (LVV). Repairs are certified by a Light Motor Vehicle Repair Certifier.