The truck is stuck in 4hi.

I need insight, please.

I put the truck into 4hi, and after about 30 seconds to a minute of driving, the serv 4wd light came on.

It was then locked 4hi and would not shift out of it, no matter what button I tried.

I disconnected the batteries and reset everything, then was able to switch to 2WD.

I got home, cleaned the actuator plug, and added dielectric grease.

It switched into and out of 4WD with no problems then (I didn't drive with it, just hit the buttons sitting still).

I then later needed 4WD again.

I switched into 4wd hi, no issues, then about a minute up the path, I got the damn serv 4wd light again.

I tried all the same tricks but couldn't get it back to 2WD or anything else. I'm stuck in 4hi, 8 hours from home.

So I pulled off the actuator, split it open, manually wheeled the fork to 2wd, and slid the axle collar over to 2wd.

I tried plugging it back in (before I installed it), and it immediately slid back to the 4WD position. Once I turned on the ignition, it would not let me slide back to 2WD via the button.

I opened it up and manually cranked the fork over to the 2wd position, reinstalled it on the axle, and then did NOT plug it in.

That enabled me to get home; the truck still shows in 4hi on the dash.

I looked for codes via the tuner, and none show; I will try to scan it tomorrow with a friend's scanner and see if it sees anything.

I hope it is just the actuator on the axle or the transfer case electric motor, but I hate to assume and throw parts at it.

All the wiring looks good; I checked the plugs, etc.

Does anyone have any insight on this?

TIA