Outer Limits 4x4 Board

Was just driving up my street and came to the end, when slowing down (fast walking pace) this loud noise happened, sounding like 2 gears or splines grinding together.
Checked all the front end and all cool
Have taken it around the block a few times and it seems to happen when decelerating in i think 1st (T700) and mostly going down hill.
Doesn't happen all the time but happens a fair bit.
Could it be something in the trans case?
Need help urgent.

Turbo 700/ LT95 trans case.

Definately first? i.e. manual shifting?

Diff Carrier bearing, Needle rollers in transfer, Auto phuched

Pretty hard to diagnise, anymore symptoms??

sure its not related to brakes binding, or crap in the pads??? Maybe jack up the wheel and rotate or even jack all of them and idle the car in first gear, accelerate and decelerate to see if you can pin point the issue - carefully with an assistant of course!!

I'd check the simple stuff first and work back to the serious stuff like TCs/GBs etc

might sound wayyyy off topic (and probably is being an internet diagnosis) but how much slack is in the bushes and ball joint in the rear??

Found it.
Mate put super hold servo in my trans the other day.
Just removed the shim in it and alls good.
He explained it to me but to hard to translate to here, has something to do with first gear and some other auto jargon.
Thanks anyway guys