While having the front and rear differential sealed, I was made aware of a U-joint (?) near the front differential loose-as-can-be-mechanic could only find a replacement through MB for $1,100.00! Could this be why there's a "clanking" sound when shifting from and sometimes while driving slowly?

This part looked to be about 1 1/2 to 2 feet long with the same joint on each end.

Any advice?

Thank you again.