[1][2][3] As built, the tender had a maximum axle load of 8 long tons 14 hundredweight 2 quarters (8,865 kilograms), a coal capacity of 5 long tons 10 hundredweight (5.6 tonnes) and a water capacity of 2,730 imperial gallons (12,400 litres; 3,280 US gallons).

From c. 1925, some Type XD tenders from Classes 6H, 6J and 8 were completely rebuilt by the SAR, by mounting a new upper structure on the existing underframe.

Since their new tanks increased their water capacity to 3,000 imperial gallons (13,600 litres), these tenders were reclassified to Type XF.

[2][3][5] The program to rebuild several older tender types with new upper structures was begun by Col F.R.

Collins DSO, who approved several of the detailed drawings for the work during his term in office as Chief Mechanical Engineer of the SAR from 1922 to 1929.