Outer Limits 4x4 Board

Have a manual dx transfercase in my 80 series was playing on the weekend in lowrange put it in highrange for a bit than tried to go back to low and just wouldn't do anything oil is full no grinding noises at all anyone got any ideas ive spoken to John at Jmac and its got him stumped till he has a look at it

My understanding is that near all transfer cases run off two cables. These select between 2wd and 4wd and then lo/hi. You have to look at the cables to see if there is a issue there. Sure to be a pain in the ass unless you have midget hands.
Other than that it may be a internal selector arm or whatever they use.
Never looked at a 80 case or pulled a case apart, so i could be way off.

Do you have neutral??

There is a ball looking joint under there someware that gets full of crap or a pin falls out or something.

I know its vague but its on the transfer box selector system,

I got stuck in neutral long time ago took it to someone who knew what they were doing and were to look and they belted ball joint on fence to get of of crap and all was good ever after. this was on a '47 probabaly similar
Is simple and cheap to fix . carton type of job.

Well we pulled it apart and I'd stripped the low range gear someone had had it apartin its past life and wasn't lined up properly