Helllo all, I wanted to share what looks like the resolution to my issue. I had the same symptoms as most of you. 2017 Ford Exp Sport, 130k+ miles. Long story short the problem started and stopped around tires over months. The transfer case tolerance on tires is 1/8, one service advisor told me is was 1/16. Either was though it is an expensive troubleshooting step unless the damage is already done replace all 4 tires and see where you stand. Sidenote: for those who have extended warranties, you need to do this step! Per the official process if your transfer case is bad due to this, you can still be covered under the warranty. However, if the Ford adjuster documents that you have mismatched tires. This will void this part from your warranty. Hope this helps at least one of you out there. -Blessings in Christ.