5570 4WD Issue

[MsBehave]

My 5570 isn't shifting into 4WD. All was working fine until it wasn't. I can pull handle no problem there. Linkage all the way to transfer case is moving ok...no problem there. No weird noises, etc. Neither Owner's nor Service Manual are much help. I always shift into/out of 4WD when I'm in neutral and at a complete stop. I did notice a turnbuckle for adjusting linkage, but don't wanna go tweaking stuff unnecessarily.

Any suggestions? I'm buffaloed

 

[eray1066]

Is the shaft going into the transmission turning as well as the linkage? Sometimes a roll pin falls out.

 

[MsBehave]

Shaft is turning. And today when I had someone else check it out, they were able to manually rock the drive shaft and 4wd engaged. However, when in neutral, there was a distinct whine. Went away after a couple shifts on high/low shifter. 4wd also went away. I'm feeling more strongly now the turnbuckle needs to be adjusted allowing for a bit more rotation of the shaft in the side of the xfer case.

 

[dickfoster]

Shaft is turning. And today when I had someone else check it out, they were able to manually rock the drive shaft and 4wd engaged. However, when in neutral, there was a distinct whine. Went away after a couple shifts on high/low shifter. 4wd also went away. I'm feeling more strongly now the turnbuckle needs to be adjusted allowing for a bit more rotation of the shaft in the side of the xfer case.

Let's hope that's all it is. Otherwise it sounds internal.