The price at the pumps has nothgin to do with the aussie dollar being cheap or expensive. There is currently a crude oil surplus in the world which means that a Litre should not exceed $1.20 max. The reason behind high prices is government taxes. Aussie and US governments charge like $0.90 tax per Litre and regardless of the barrel price of crude oil, the price at the pump will not go down unless greedy governments stop charging rediculous taxes.
There you have it....