Mass Limits

State and National Road Authorities set weight limits for axle loadings based on design considerations of the roads infrastructure. Vehicles must not exceed the lesser of:

  • The manufacturers GVM / GCM
  • The maximum statutory axle mass limits for individual axles or axle groups and the sum thereof.
  • Manufacturer’s maximum placarded tyre loading.
  • The posted weight of a load restricted road or bridge.

Typical examples of combination weight limits

Axle configuration Total mass limit (tonnes)
truck 15 15
truck 22.5 22.5
truck 42.5 42.5

Full details are set out in the RTA National Heavy Vehicle Reform brochure “Heavy vehicle mass, loading and access” [RMS catalogue No RMS45070666D 96/99)] available at Roads & Maritime Services or at

4th Power Rule