I just had some 4.88's installed on my 77 k5 the other day by 4x4 company and I was wondering how you could tell if they did the jobe right. There are some strange noises coming form the rear end and driveshaft. With the truck in neutral I can rotate the driveshaft alot farther than I have ever seen before. I was just looking for some answers. My t-case was just rebuilt and the U-joints are brand new just so you know. Didn't want you to think that that was the problem. Any info would be greatly appreciated.