Green’s Dictionary of Slang

(Aus.) a bus.

1968		J. Alard He who Shoots Last 98: Dere’s an Uncle Gus leavin’ in an hour.
1989		R.G. Barrett Boys from Binjiwunyawunya 292: Only brokies and backpackers doing it on the cheap ever catch the Uncle Gus.
1998		R.G. Barrett Mud Crab Boogie (2013) [ebook] I’m off to the old steak and kidney in the uncle Gus.