[3] After serving on Lord Carver's staff during the Rhodesia talks in 1977,[3] he was promoted to lieutenant colonel on 30 June 1978.
[9] He became commanding officer of 2nd Royal Irish Rangers in 1979 and led his battalion in Belize, Gibraltar, Berlin and Canada.
[3] Having been promoted to full colonel on 30 June 1982,[10] appointed a Commander of the Order of the British Empire in the Queen's Birthday Honours List 1983[11] and promoted to brigadier on 31 December 1984,[12] Wheeler went on to be commander of 11 Armoured Brigade in British Army of the Rhine in 1985.
[23] As CGS, he was responsible for implementing the Strategic Defence Review after the new Labour Government came to power[24] as well as providing strategic military advice to the British Government on the deployment of troops for the Kosovo War and in connection with the formation of the United Nations Transitional Administration in East Timor[25] before he retired from the British Army in 2000.
[33] In retirement, he became a Non-Executive Director of Thales plc, a Non-Executive Director of Aegis Defence Services and, until 2009, a member of the governing board of the Serious Organised Crime Agency as well as President of Combat Stress, the mental welfare society for ex-servicemen.
[3] In October 2009 he was appointed advisor on military matters, to the British Government's inquiry into the Iraq war (headed by Sir John Chilcot).