Yeah, I just did it (even though it was under warranty, it would require more time to 1: call, take appointment. go there, wait for them to check. go back, bring it back for them to replace, oh god...
It's quite easy. Mine was badly rusted so it required penetrating oil to remove nuts.
remove rear wiper arm.(I needed a gear puller for that, it was rusted in the splines), remove rubber boot,
then unbolt the large bolt, then in the cargo space, remove black cover, then remove 2 bolts holding the assembly, unplug, and you can remove the whole assembly.
Bring on bench, open the whole thing, remove gears
Now, what's left is the shaft in the housing.
Mine needed a pair of vise grips to turn.... Oil it, then I had to hammer it inside
Then you remove the whole shaft assembly by the inside.
Then I used a wheel brush to clean the heavy rust on the shaft.
(The wise way to do it is to remove most rust before trying to hammer it in....)
Then, basically, just grease everything and assemble. It now turns with the fingers.
There is a timing mark that you need to check when reassembling, just align the 2 triangles on the gears.
It's dark outside and mosquitoes are out, so I will reassemble tomorrow morning and report.
I will use silicon grease inside the boots to prevent water damage to shaft.
It takes around an hour to do.
2011 Grand Cherokee Overland V8, QD, QL
Nokian Hakkapelita 8 SUV Studded winter tires