Clunks when shifting from park

Hey there. I've got myself a 97 4.0 AW4 NP231 with 227000 on the ticker. When I shift from park into anything, whether it be drive or reverse, I get a very loud and disturbing CLUNK. Afterwards the tranny shifts like a dream. I also get the clunk shifting from reverse to drive or vise versa. Any thoughts?

tranny mount for sure :cheers:

How are the u-joints in the rear driveshaft?