The one I use is called "REESE Teflon Hitch Ball Lube", Part No. 58117. I think I got it at Camping World but it could have been another RV supply place. I've had the 4 oz. container for about 10 years and use it on my 5th wheel pin now. Just a little dab will do ya', like Brylcream for us old timers. I have a teflon plate to lube the rest of the fifth wheel plate.
Dan