Nut for rear strut rod adjusting bolt

So in removing one of my rear strut rods, when taking off the nut to that camber adjusting bolt, the nut was hard to turn all the way to off.

Is this some sort of a lock nut, or are my threads a little booger-ed up?  I'll run a die down the threads on the bolt to clean them up, I'm just wondering if the nut is supposed to be hard get off once it's loosened as it has a lock washer under it.  The threads weren't dirty or rusty.

Hi, If it has a plastic type of outside edge, it's a nyloc nut. They are designed to be a lock to keep from loosening up. OR it could be a squeeze type of nut. The front rounded edge is pinched in, and is the same locking type design. If it's a castle nut with a cotter key slot, and still moves dificultly, something is probably not right. Run a tap in the nut, and a die over the bolt. Should correct the problem. 

That's what I did.  Wasn't a nyloc nut or pinched so I ran taps and dies down everything.  I'm 3/4 of the way done.

My strut rod bushing were beyond shot and completely worn out.  Should have done this 5 years ago. 🙃