4wd not engaging but actuator works

[Dante2795]

4wd was working perfect yesterday in the snow. Today, I tried pulling my trailer out of the snow and 4wd wasn’t engaging. (Electric tcase)
-Tried 4low and truck goes into neutral and coasts
- 4x4 switch works as it should. Can hear transfer case
-front actuator works
-no service 4wd light
-tried doing the reset, didn’t help.
Now when I jack up the front end, and put in 4high I can spin the driveshaft and one wheel will spin.
If I spin either front wheel, the drive shaft spins

Any ideas? No strange Noises, no service lights, can hear transfer case and front actuator engage

 

[DAVe3283]

What you describe for 4Hi is correct. The front diff is open, so spinning the driveshaft will only turn one tire.

The actuator might be going bad, and didn't go into 4Hi the first time. When you select 4Lo and get neutral, that sounds like the feedback circuit inside the actuator is going out. I'd consider replacing the actuator.

 

[JoshH]

Put it in 4wd and jack up the front tires off the ground and try to turn the driveshaft by hand. If you can turn the driveshaft, you have a transfer case problem. If you can't turn the driveshaft, you have a front axle problem. You should be able to narrow it down from there. If your truck was having strange engagements into 4 low, I would suspect something transfer case related.

 

[Mike L.]

Bad Fork?