I noticed that my 98 4WD leans to the drivers side about a inch or so.... how can I fix it. Its driving me crazy

 

Check the shocks...?
You can try the rocking method my getting the car rocking back and forth and see how many times it continues after stopping... it shouldn't be more than twice, and should quickly stop. When was the last time you replaced them(if ever)? Anyone else want to chime in on this one??

 

Do you have a lift on your rig? If so, it is most likely due to the fact that the panhard bar is slightly pulling your axle towards the passenger side. The panhard has one end attached to the body of the truck, and the other end attached to the rear axle, and its purpose is to center the rear axle under the vehicle. However, if you don't have a lift, I'm not really sure what the cause may be. Take a look under there and see if anything looks out of whack if you haven't already.