yep, it was the speedo cable, took 30 seconds to unscrew from transfer case, drove around the block, silence!!
unreal how it can make such a squealing racket
many thanks for this thread being here and Cory inparticular.
the noise got me $500 dropped off a 2002 hilux btw, was a complete mystery, I figured $500 worth of mystery, now it's just a couple of hours to pull the dash off and unclip the speedo.