Union Castle Line

great pic, do you know anymore about her.

Yes I do.
The Dunluce Castle specifications are
Tonnage 8,114 gross
Launched April 31st 1904
Builders Harland & Wolff Belfast
Listed as a"D" Class Intermediate Liner.
In 1915 she was converted into a 755 bed hospital ship.
In peacetime she carried 230 first class passengers, 270 third and 300 steerage.
Disposed of in June 1939 by Union Castle, and sold for scrap, she however was spared this inglourios end and spent the Second World War years as an accommodation and depot ship at Scapa Flow under Admiralty control.
In 1945 she was scrapped at Inverkething.

His Majesty's Australian Transports [HMAT] Ships
A fleet of transport ships was leased by the Commonwealth government for the specific purpose of transporting the various AIF formations to their respective overseas destinations. When not committed to military transport, these ships were employed to carry various commodity exports to Britain and France. The fleet was made up from British ships and captured German vessels.
SS Dunluce Castle
http://alh-research.tripod.com/ships_lh.htm

Record Summary
Scope and content Hospital Ship, Dunluce Castle
Covering dates 1917 Jan. - 1919 Apr.
Availability Open Document, Open Description, Normal Closure before FOI Act: 30 years
Held by The National Archives, Kew
This of course is the official war diary or official copy of same for this hospital ship in the latter years of the war at Kew (as per requested).
For the former Board of Trade (later Ministry of Transport) see:
Transport Dunluce Castle. Military Commanding Officer's Voyage Report Cape Town to Southampton; remarks regarding `Horse Fittings'. `Drainage', `Ventilation' etc. 1914
MT 23/408 Collision of S.S. Dunluce Castle with S.S. Neuralia. Masters' report, responsibility for damage. 1915
MT 23/485 Hospital Ship Dunluce Castle. Details of personnel and stores conveyed to Salonica. 1916
W.O. 95 / 4143 Lines of Communication War Diaries WWI
Dunluce Castle 1917 1919