Deiveshaft/rear end clunk

[MTF]

This has been an issue on my '12 SCrew almost since new. The slip yoke greasing does work for a bit but as the grease works its way through the splines and eventually into the transfer case, the clunk comes back. Periodic re-greasing of the splines is a must....just one of those things that you have to live with.

You may still have one of the slip yoke that wasn't nickle coated properly being a 2012.
Ford changed the slip yoke in 2012, you still need to grease but not more than once or twice a year.