I got a 97 k1500 with a 4x4 on the floor, I used the 4x4 to go up a icy hill then shifted back into 2wd going about 15mpg. I drove 10 miles no problem then i passed a car and i heard a loud pop at about 65 and then I punched it and got up to 65 again after I got on a new road to see if I could hear it again and It sounded like it was coming from the front end, and It made the noise like something metal was clanking, when I got home I tried to put it in 4hi and I couldn't move the lever I just hear a noise of something moving under the cab but it wont go far enough to get into 4wd same goes with low. I also wiggled my front drive shaft and it spins all the way around easily is that normal? any help would be nice cause I'm at a lose.