my 87 sammy always pops out of 4wheel drive high,,,does anyone know the reason why,,,it works fine in low lock,,,and i can hold it in high,but pops out randomly,,,thanks

 well im guessing here  but normaly  a transfer poping out of gear  id do to a bent shifting fork

has the case been opened before? there are some shifter balls and if someone took one out then it wouldn't hold as good as stock.

take the boot off and see if the shifter is hitting I ran into the same problem I took a sawssaw and cut it where it wouldn't hit any more boot covered it and never pop out again

did something get bent? are the t-case mounts broken to make the case twist? There is a reason for the contact. You can run a zuke for a long time with one broken mount but as soon as you break the second then you're screwed.

You might check the mounts too.  I picked up a Ford cheep because it would not stay in 5th.  I lent it to a buddy of mine and when I watched him back it up I could see the whole motor move underneath.  Turned out it was a busted motor mount.  Replaced it and sold it for a tidy profit.

It's prob. the shifter sheet.

Mine did this...and the next time out wheeling- stuck in neutral.

Pull knob, boot, 4 bolts, shifter. You'll most likely find a mess of black goo that used to be the bushing...