WARNING: This page is about a different car, the 2008 Infiniti FX45 and 2008 Infiniti FX35. However, it is still accessible from the selected car via links, so may be relevant.
Check items below. If necessary, replace them with new one.
Damage, peeling, dent, uneven wear, bending, etc. of shaft.
Fig 1: Identifying Damage, Peeling, Dent, Uneven Wear And Bending Of Shaft