4x4 low all on its own!

[DeepVee]

My '16 3500 recently wanted to go into 4x4 low all on its own. On the freeway!!
We were pulling our large travel trailer on I-40 and just about to exit in Kingman AZ for the night. As I was slowing for the exit, there was a horrible noise. At first I thought we were dragging something, but then quickly realized it was coming from the truck. The moment I hit the off ramp I stopped, as did the noise. But, I now see a dash warning "service 4x4 system". (this light is what makes me think it was trying to shift to low).
As I rolled forward a bit, the warning light went out and no noise. We continued on for another 2 miles to our overnight campground. Our site was gravel, so I put the truck in both 4x4 and 4x4 low. All seemed well. At this point, I determined which fuse controls the transfer servo motor and removed it. We continued our journey without incident.
Rather than take it to the dealer, I'm going to stop by my trusted transmission shop and get their opinion.
Two things: What caused this, and what (if any) damage may have happened?
My brother found something posted on internet regarding the same failure, so I'm not an isolated case.
I'll let you know what I learn.
Dave

 

[DeepVee]

Taking suggestion of trusted transmission shop, I visited the dealer. Not a lot of help. I was told they have no way to know if there was any damage. If I wanted to have transfer case drained to check for evidence, it would be on my dime. He did check codes and found 3.
With 30,000 miles on the truck, I think I'll have the transmission shop do a transmission service and also change transfer case being careful to capture the oil to examine.

 

[huntergreen]

I might just leave it and if it happens again, not the gas has and destroy the transfer case while under warranty. Then they will fix it.