AC/DC's musical formula hasn't changed much over the years, and for good reason: For 40 years and counting, Australia's loudest musical exports have decisively proven that you don't need much more than a couple of guitars, a couple of chords and a dirty mind to make great rock 'n' roll.

But while the band's sound has remained steady over the decades, the names and faces behind the music have undergone more than their fair share of turnover, and that's where this installment of Lineup Changes comes in. We're taking a chronological look at the ins and outs of life in AC/DC, from their earliest days as struggling unknowns to their current status as one of the reigning kingpins of rock.

During the 2015-2016 Rock or Bust tour, three different members of AC/DC were taken out of action by serious medical problems (Malcolm Young, Brian Johnson) and legal issues (Phil Rudd, arguably self-inflicted) over the past couple of years. Only two of the five members who recorded 2008's Black Ice performed on the final dates of the group's Rock or Bust tour – lead guitarist Angus Young and bassist Cliff Williams. In order to complete that temporarily postponed trek, the Australian legends called on help from the singer of another famous group known for their numerous lineup changes: Axl Rose of Guns N' Roses.

Grab your amp and your schoolboy uniform, because it's time to get started with our most ball-breaking Lineup Changes yet.

You Think You Know AC/DC?

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