twoshoes

We got an 04 burb a while back with a 5.3 liter and 4x4. When I got it the 4x4 indicator light showed it was running in 4 low when indeed it was not. Even at highway speeds the light was on. At times it would say it was in neutral and 4 hi and 4 lo even when I was driving down the highway. At times I could stop and put it in neutral and all the 4x4 buttons would work correctly and it would shift in any range I pushed and the 4x4 would work fine. I replaced the 4x4 switch with a dorman and it did not change anything, service 4x4 light still on and light would show different ranges were on when indeed they were not. I didn't worry to much about cause I would rarely need the 4x4. We took a 700 mile trip last week in it and everything was flawless even tho at times it showed it was in 4 lo at 75 mph. So I got a new hitch for my camper today and wanted to mount it and go out for a test tow pulling my camper weighing 5,000 pounds. Its the first time I had pulled camper with the burb and (I did have burb in tow mode). I drove 8 miles on 2 lane roads at 55 mph and then 7 miles on interstate at 65 and then started 8 mile trek back home on another 2 lane road at 55 and I began hearing an off and on clicking noise and possibly a lurch each time I heard the noise, It was hard to tell. I heard it every 10 to 15 seconds. The 2hi light had been on the whole trip. There was no place to pull over for a long while so I drove slow with window down and listened and Im thinking the clicking was coming from under front of burb. I just felt like the 4x4 was trying to engage but I can't be sure. So when I got to a place I could stop I put burb in neutral and pushed 4hi and 4lo and no response at all. I shut the burb off and turned it back on, put in neutral and pushed 4 lo and felt it engage, went back to 2 hi and felt it disengage, did the same for 4 hi and back to 2 hi and also felt engage and disengage.
So I took off again and the clicking was gone. I am just wondering what else could be wrong besides the switch? Thanks for the help.