Wondering what this noise is. If anyone has some insight into what it could be I would appreciate it.

Took it into the mud and it was there for longer than I would have liked before it was winched out. I replaced all fluids etc. but then I had a wheel bearing wobble so I did the front wheel bearings. However when I get up to 60 mph or higher on the highway and let off the gas I get this grinding strange noise. I had this noise before replacing front bearings and the noise is still there after replacing them. Wondering if my exhaust is somehow loose somewhere or what. If anyone has an idea of what it is I would really appreciate it.