TC wrote:
My trailer hitch has to be greased to slide over the ball (yes they are
the same size). Then it's a real B*%#ch to get the lock to lock. Could
this be due to the fact that the chrome on the ball is gone or could it
be that the trailer tongue lock is set too tight?

If it's too tight, there is a nut on the underside that you can loosen.
Check the play in it when it's locked.

It sounds like it is too tight if it scraped the chrome off. Before I
couple mine, I push the shackle in the coupler back to be sure it
retracted all the way. I end up with greased fingers though.