Re: clunk coming from drivetrain (rear end?)
heyiwantthatphotomaccom... You don't need that!
You have an ARB front and rear and don't need friction modifier.
You are asking about normal drive shaft rotational play. The differential end should have some back lash and axle spline slop that will let you rotate the shaft several degrees. The transfer Case end can have a little more.
Four time Baja 1000 winner, four time Baja 500 winner. Solo'ed the Baja 1000 to LaPaz/Cabo twice.
4-Wheeling since 1972, Desert Racing since 1989.