How long was Axl Rose with ACDC?

Excuse me, but I believe there might be a slight misunderstanding in the question posed. Axl ROSE is best known as the lead singer of the rock band Guns N' Roses, whereas AC/DC is an entirely separate band with a different lead singer, Brian Johnson. AC/DC has had a long-standing and successful career, but Axl Rose has never been a member of that band. So, to answer your question, Axl Rose has never been "with" AC/DC. Perhaps you were thinking of another band or artist?