There was a reason I gave you 4 different tests to try. If you want to diagnose what's really wrong, do all of them and report results. If you LOCK the pinion gear by putting it in park, and the wheels rotate at all, the rear diff is NOT locked. If it was locked, you could not rotate the wheel because there is no differential action - its LOCKED by the locker and the park pawl in the tranny. And it's not the first time a mitsu dealer made a wrong diagnosis....

Curtis has as good a mechanical knowledge as anybody who ever worked at a mitsu stealership. Why not listen to him?

Not responsible for advice not taken...