Grinding/vibration from rear end

[jiffylube700]

I have a 2019 Ram 1500 tradesman With limited slip differential that started a consistent grinding/moaning sound with vibration when turning at slow speeds in the rear end after having the fluid swapped at service a few months ago. Only starts after it warms up at around 10 miles and is primarily when turning from a stop, but after driving all day will do it at low speeds without stopping. During the service, the dealership didn’t put in a friction modifier and was immediately noticeable when I left when the rear end was almost skipping across the road with vibrations and very loud grinding. Took it back and they added the modifier and it stopped for about 2 months. Sounds and vibrations are back. I’m trying to add a video soon. Any ideas?