Hi Paul; follow this link, www.convert-a-ball.com
And yes, my Hensley has a hexagonal shaped stud, with a hole through it near the top, welded to the top plate. A ball with a hexagonal shaped opening and a pin hole drilled through it from side to side, slips over the stud, and a pin is inserted into the ball, through the stud, and flush with the other side. This ball is what is loose on my hitch. I knocked the pin out, took a picture, and sent it to Hensley. Yesterday, I was assured that the pin was in good shape and the ball, even when new, had a lot of 'play' in it. Today, with the pin out, I noticed the hole was obstructed, and driving a punch through it, another piece of pin came out; the pin was obviously broken. I've taken new pictures and sent them along with a lengthy e-mail to Hensley. Hopefully, I'll get this resolved on Monday. Also, when my hitch was installed, I had a zerk fitting installed in the top of the coupler and do not need to drop the hitch in order to lube it.