2nd Gen 4Runner… Noise when 4wd is engaged

Hey guys, first time posting here so if I mess something up sorry I’m advance. I have a 1991 4Runner that makes a sort of clunky noise whenever I engage 4wd. Goes into 4wd no problem. No grinds or pop outs. Just makes the noise when rolling.
Tried attaching a video of the noise, hopefully you can hear it well.

well video doesn’t attach but can email if someone is willing

 

Does it sound closer to the front, middle, or back?

 

Sounds like it’s coming from the front