Geoff, and anyone else that needs something on the threads of their Pentax XL's, I just applied a small amount of vasoline to the threads of my 7mm Pentax XL and the motion is now smooth!!!...I used a small amount with a very small model paintbrush and applied it sparingly to the middle of the threads of the EP after dissassembling it.
It now turns like a factory pentax XW
Give it a go, you'll be surprised
