The GH class high-sided open wagons were used quite extensively for grain traffic and it was decided to fit roofs to some of these wagons. This conversion was similar to that which created the RCH class from the RCW's.
Ten GH class wagons were involved (18440/8, 18469, 18495, 18515, 18542, 18628, 18646/8, 18672). They were written off as follows:
1977 - 18648
1979 - 18515
1985 - 18628
1987 - 18469, 18646
1990 - 18440/8, 18495, 18542, 18672
