I am a new member here hoping to find some help on the 4wd on my zr2. I've had this truck about 4 months and when I first got it it was making a whining/grinding noise but more of a whining noise from the front end but it only did it every once in a great while and all you had to do to get it to quit was stop at a stop sign or hit the 4wd button and shut it back off and the noise would go away. Somedays it would do it somedays it wouldn't do it all, but then it got worse and it wouldn't make the noise unless you had it in 4wd full time it wouldn't make the noise, then it got to making a banging felt like you were hitting a bump kinda noise in the front end when it was in 4wd but it only would do it when u were accelerating from a stop up to about 40 mph then it would stop going down the highway till you stopped and sped up again. I took it to a shop and he just put a new actuator in it yesterday and that didn't fix it. I was wondering if anyone here had any ideas what was causing this so maybe I could tell the mechanic so he would have a little more of an idea what to look for. I really hope someone can help me on this. Thank you very much.