This is not a common problem as I have not located a tech service bulletin on it. There
are so many things that can make a clanking sound from drive shaft to suspension
and transfer case and transmission and more. I would take it to a exclusive trans
mission shop and for a diagnosis and ask that they call you with cost and for permission before any
repairs are done. If you had it in 4x4 when it started it is probably the transfer case or differential.