I purchased the remains of an ex-mil no.5 trailer in early 1991 in Townsville. One of its faults was an axle with a shattered cast iron hub, probably because the original Landy wheel studs had voluntarily removed themselves while still moving.
As I have always towed this trailer with a restored 1981 Nissan KR160 Patrol (MQ Shorty) which has a wider track than a landy or No 5, I gave the original axle to a grateful Landy owner. I had a spare Nissan MQ front axle lying about, so it was a no brainer to follow the no. 5 OEM axle idea and improve on their design.
I fabricated a 50mm bright mild steel axle with a machined flange welded each end to allow Nissan MQ Front Stub Axles to be mounted using the same track as the tow vehicle.
In 2016, I retrofitted Nissan MQ/GQ discs and calipers. Powered by an Alco IQ7 air over hydraulic actuator and controlled by a Redarc Tow Pro Elite controller it is a brilliant combination.
There are many advantages to this approach which allows the use of the Nissan hubs, discs and callipers. Increased track and choice of wheel or tyre sixe for example.
I used this axle for 23 years before refitting the discs to the Nissan Rotors, largely because of a recent trailer length increase and weight; and because of a scare I had in 2014 on the Maytown to Laura coach road.
I can post pictures of the axle if required.