In January 1975 the battalion deployed to Darwin as part of the clean-up following Cyclone Tracy. Between 1976 and 1978 5/7 RAR trialed a mechanised infantry organisation using M113 armoured personnel carriers. The value of this mechanisation was demonstrated when the battalion was able to quickly respond to the Sydney Hilton bombing in 1978 by guarding the route between Holsworthy and the site of the Commonwealth Heads of Government Regional Meeting at Bowral. While the mechanisation trial was judged a success, it was decided that only one of 5/7 RAR's companies would be mechanised, with the mechanised role rotating between the battalion's rifle companies every 12 months. The battalion was fully mechanised in 1984 and in 1986 the battalion's official title was changed to 5/7 RAR (Mech).