He was almost ousted in a coup
As the leader of the SPLA, Garang almost became a victim of a coup orchestrated by his own commanders. Lam Akol, Riek Machar and Gordon Koang Chol were behind this attempted coup of 1991.
Not many people knew of the coup until it was announced by the BBC on August 30 even though it started on August 28. Although it was unsuccessful, it highlighted some of the issues in the SPLA that needed to be addressed.