Mine too is off half an inch on the passenger side.

 

Well, took it to the shop and had springs tested. They're fine. So I loosened my bed bolts and shifted the bed a bit and it helped a little. (not enough) I decided to try washers (2) between the bed and frame on the right side... tightened the bed bolts back down and... it was level. Hope this helps you other guys.

tdub