2021 Telluride, AWD and towing package.. at about 30k miles, started hearing faint thump in rear end when barely moving, on passenger side. Going over the slightest bump would hear it. Have had it up on ramps for the last hour, and FINALLY think I've found the culprit. After finding that both rear axles can move back and forth with little force, it wasn't the same sound. As I pushed up and down in the rear end from under the car... I found it. There is a dust "boot" that covers half of the shocks. When I tugged on the passenger side one, the sound appeared!!! I twisted it and sound stopped. I've got it scheduled for service next week, and see what the fix would be, but thankful I think i found the sound.... without replacing shocks and or suspension.