In 1972/1973 the railways recoded the fleet of GJX_ bogie grain hoppers. As the GJX wagons were suitable for standard gauge running the wagons saw traffic interstate to NSW. Unfortunately they stayed in NSW, leaving Victoria with a grain hopper shortage. To prevent the wagons leaving the State they were recoded to GJF with removal of "Grade Control" equipment.
After some recoding the number group for GJF was 21 - 200 with 201 - 350 built new. Numbers 1 - 20 were retained for GJX.
With the 1979 recoding, the GJF wagons were recoded to VHGY
Numbers 21 - 100 were aluminium construction. 101 - 350 were built of steel.