Axle codes

The number of axles in the tables in this section are derived from the axle code shown on the vehicle’s Certificate of Registration. This code is used to record the layout and number of axles and wheels on vehicles. Non-driven axles are included (eg retractable, tag, lazy, pusher axles etc).

For registration charging purposes, the calculation of the number of axles is as follows:

  • two axles not more than one metre apart from the wheel centres are treated as one axle
  • four axles not more than 3.2 metres apart from the wheel centres are treated as three axles
  • three axles not more than two metres apart from the wheel centres are treated as two axles

The illustrations on this page represent examples of typical axle layouts and the corresponding axle code.

Trucks, prime movers, buses

Axle layout Axle code
Axle layout for R11 code - 2 at the front and 2 at the back R11
Axle layout for R12 code - 2 at the front and 4 at the back R12
Axle layout for R19 code - 2 at the front and 2 sets of 2 at the back R19
Axle layout for R13 code - 2 at the front and a set of 2 and a set of 4 at the back
or
Axle layout for R13 code - 2 at the front and a set of 4 and a set of 2 at the back
R13
Axle layout for R14 code - 2 at the front and a set of 2 sets of 4 at the back R14
Axle layout for R15 code - 2 at the front and a set of 2 and two sets of 4 at the back R15
Axle layout for R16 code - 2 at the front and three sets of 4 at the back R16
Axle layout for R22 code - two sets of 2 at the front and a set of 4 at the back R22
Axle layout for R24 code - two sets of 2 at the front and two sets of 4 at the back R24
Axle layout for R26 code - two sets of 2 at the front and three sets of 4 at the back R26
Axle layout for ZAV code - articulated bus with three axles ZAV
Variable axle configuration for ZRT code - 3 or more axles ZRT

Trailers

Axle layout Axle code
Axle layout for T1 code - 2 axles T1
Axle layout for T2 code - 4 axles T2
Axle layout for T9 code - 2 sets of 2 T9
Axle layout for T3 code - a set of 2 and a set of 4 axles T3
Axle layout for T4 code - 2 sets of 4 axles T4
Axle layout for T0 code - 3 sets of 2 axles T0
Axle layout for T5 code - a set of 2 axles and two sets of 4 axles T5
Axle layout for T6 code - three sets of 4 axles T6
Axle layout for T8 code - four sets of 4 axles T8
Axle layout for T22 code - 2 sets of 4 axles
or
Axle layout for T22 code - 2 sets of 2 axles
or
Axle layout for T22 code - a set of 2 and a set of 4 axles
T22
Axle layout for T24 code - a set of 4 axles and 2 sets of 2 axles
or
Axle layout for T24 code - 3 sets of 4 axles
T24
Axle layout for T44 code - 4 sets of 4 axles T44
For trailers with 5 to 9 axles T1#
where # is the number of axles on the trailer.

Self propelled plant and SPVs

Axle Layout Axle code
Any P#
Where # is the number of axles on the vehicle.
Share this page: