Despite the trials of SFX_ 100 with the tarpaulin retractable covers, the VFNX wagons were prone to many failures. The VFNX wagons were placed into service in 1979.
To overcome the costly maintenance involved, new equipment was placed onto the wagons during 1993. Fourteen wagons were fitted at Bendigo Workshops. The class for the modified wagons was designated VFPX with numbers 1 to 14.
The numbers do not follow the VFNX number group, though VFPX 1 and 3 were converted from VFNX 1 and 3 respectively.
File c485m compiled by Peter J. Vincent, updated 25/11/2007