Greasing the hub Spline of Clutch Disks

If the clutch disk is not greased correctly when it is installed, then fretting corrosion may occur in the hub spline. In this case, the clutch disk will seize instead of sliding along the transmission input shaft. For this reason, ZF Services expressly points out that it is imperative to grease the spline profile correctly. This allows the clutch disk to move freely along the profile of the transmission input shaft.