Allison 6 speed issues.

[BIGR]

Well. @Lennydmaxguy hit the nail on the head. I dropped the front drive shaft, took the encoder motor off, manually shifted the transfer case (counterclockwise) 2 clicks until it didn't go any further, took the encoder motor apart, lifted out the big gear and rotated it clockwise about an inch so it would line back up with the transfercase shaft that I manually rotated, buttoned it back up and everything works as it should.
I am shocked. I shifted from 2wd to 4wdH and back. I didn't try 4wdL. I'll do that another time as I need the truck.
No codes, I think I was the one who caused it from not placing truck in N when going from 4wdL to 4wdH.
In any event, this has been a learning process. Hope this helps anyone else if you ever encounter this issue.

Wow, sure glad you got it fixed. Atleast I have an idea what to do if my truck does the same thing. I very seldom put it into 4wd-Lo, but use 4wd-Hi, pretty regular going up the driveway. Once in a while I put it into 4wd-Lo, just to make sure it's working. Truck has so much grunt in 4wd-Lo, I think it would pull a house, Ha, Ha.

 

[RI Chevy Silveradoman]

LOL. I was using it to pull down some trees that were hung up.
When I shifted from 4L to 4H I was not in neutral. When I realized that I quickly shifted the Allison into N but the transfer case didn't seem to shift. The whole truck then just stayed in N. My fault as I knew I should have been in N before I tried to get out if 4L.
The 4L really is stout! I pulled some big 36-40" diameter trees over and down. Truck never even sweated.
Interesting note: it seems that as soon the transfer case realized there was an issue, it sent the Allison into a fail safe mode of N. All electronically. I'd much rather have the transfer case shifting done mechanically rather than electronically.