Heavy Vehicle Mod Inspections
Your trusted expert for heavy vehicle modifications — NHVR code of practice compliance for vehicles over 4.5 tonne.
We love working with small businesses — from construction companies and pest control, through to tree lopping, event managers, butchers and florists. It doesn't matter what you drive, we keep you legal.
What classifies as a heavy vehicle?
Vehicles above 4.5 tonne in weight are classified as heavy vehicles. The National Heavy Vehicle Regulator (NHVR) outlines in the code of practice that any modification that may affect the safety of the vehicle, if not performed properly, needs to be inspected and approved by an Approved Person.
Get in touch with us to see if the modifications you are wanting to perform need approval.
Modification Codes
Common heavy-vehicle mod codes we inspect & certify. Unsure if your build needs a plate? Give us a call.
- A1 – Engine substitution
- A2 – Air cleaner sub or additional fitment
- A3 – Turbo charger installation
- A4 – Exhaust system alteration
- B1 – Transmission substitution or additional fitment
- C1 – Tail shaft modifications
- G1 – Relocation of air brake components
- G2 – Installation of trailer braking controls
- G3 – Trailer brake system upgrade
- G5 – Auxiliary & endurance brakes
- G6 – Air-operated accessories
- G7 – Brake system substitution / wheelbase extension
- H1 – Wheelbase extension outside OEM
- H2 – Wheelbase reduction outside OEM
- H3 – Wheelbase alterations within OEM
- H4 – Chassis alteration
- H5 – Trailer chassis modifications
- J1 – Body mounting
- D1 – Rear axle installation
- D2 – Differential substitution
- E1 – Front axle installation
- F1 – Suspension substitution
- F2 – Trailer suspension mods
- K1 – Seating, seat belt & anchorage alteration
- K3 – Cabin conversion
- K5 – Wheelchair occupant restraint system
- K6 – Child restraint anchorage installation
- P1 – Tow bar & coupling install
- P2 – Fifth wheel & king pin install
- R1 – Vehicle mounted lifting systems
- R2 – Wheelchair loader installation
- S1 – GVM / GCM re-rating with S2 design file number
- S7 – ATM / GTM re-rating