The Beijing - Taiyuan line sees a reasonable amount of freight traffic for a secondary route, most of it coal from mines in the west to the Beijing area. DF4 5212 and DF4D 4030 crossed one of the viaducts west of Gougezhuang with a loaded coal train on 30 September 2006. The first loco was a Ziyang built DF4C and the second a Dalian built DF4D, both based at Fengtai, the massive freight yard in southern Beijing. Fengtai based examples of these two classes shared freight workings while I was there. They were usually single headed but sometimes ran in pairs, as on this occasion.