I know my title is misleading. What is going on is when I put my k5 in four wheel drive it acts like the tires are rotating against each other, they are slipping. It is the same type of slip that you get when you make a tight turn in 4H or 4L. When you make the tight turn the inside tire tries to turn at the same rate as the ouside tire, but can't because it is traveling a shorter distance so it slips back and forth on the geound as a result of the extra force. This is what both sets of wheels are doing when you have it in either 4HI or 4LO just driving straight. Its as noticable on dirt, but on pavement you have to force it to move. I just had the rearend rebuilt so I figure that has something to do with it, because it has never done this before. I know the the new rearend is an aftermarket positrac, and it replaced the stock limited slip. Would that make any difference. I really don't know the difference between the two anyways, but thats another story. I'm pretty sure the ratio he put in was right, but I didn't count the gears myself so I don't know, but hopefully the guy is at least that smart. If you guys have any ideas what it might be, driveshafts not aligned right or what ever, I'd really like to know so I can tell him what to look for or at. Anything past the motor is out of my league so I appreciate the help.