I have a 2018 with the 6.2l and 8 speed. I had the shudder issue pretty bad. Mine was mostly the "rumble strip" experience. If I was driving at a steady speed the transmission would "load" like it was going to shift up, then never shift, which would cause the truck to feel as if it was driving over a rumble strip. It did this every minute or so. It was terribly worse when towing. Would make the truck shake pretty good.
I had the service done with 22621 on the odo on Jan 21 2020 and it worked like a champ. I have ZERO issues now. It was covered under warranty, so I paid $0 for this to be done.
100% worth it in my opinion.