The replacement of WM2 white metal plain axlebox bearings with WM4 (TM-TRIB-026)

British Rail currently uses two white metals for the lining of plain axlebox bearings. They are WM2, an 85% tin based material, used mainly for coaching stock and WM4, a 75% lead base used primarily for wagon axlebox bearings. In 1975/77 Southern Region mounted a trial to assess the...