So I have a 2001 Chevy tracker with 4wd it's also the base 4cyl version. I noticed a few weeks ago when it was really slick that when I had 4high engaged that it made this crazy winding noise like a 5 speed car dose when it's in reverse. I took it to my shop and they said it looks like I need my belt tensioner and idler pulleys changed out. I left and let it go because they said it's not serious. So just the other day on dry pavement I put it in 4high again and now the winding noise has changed and it's now clicking only when in motion like a cv shaft does when turning. It dose not matter tho if I'm going straight or turning and the speed of the clicking follows the speed I'm doing down the road. And both noises only happen(ed) when I have 4high engaged.