The 1979 recoding relettered the ALX_ class to VMBX. Numbers were: 1 - 25, 27 - 34, 36 - 45, 47 - 57.
In 1982, VMBX 51 was destroyed at Enfield, NSW and written off in 1983.
Between 1988 and 1990 the class was recoded to VMBY.
By the 1990's the wagons were not used as traffic was going by road.
The wagons were in storage for several years before some were sold interstate for use between Adelaide and Perth.
The remaining wagons were reclassed to RMBX in 1994/1995.