Four wheel "clunk"

[86chevluvr]

Hey guys have a problem and have read similar post but they dont seem to involve my exact problem. If i put my truck in four hi or low and put a little tension on the drivetrain i get a clunk in my front end.... I say front end because it doesnt sound like its coming from under the seat or t- case area, More like front diff. When this happens i lose my front wheel drive, or at least one wheel the driver side seems as though it wants to keep turning. I changed both acctuator motors on t-case and front diff as well as drained and replaced fluid, there was a little metal on magnet but very fine. Has anyone else had something like this happen? I appreciate any help.