I have a 2001 Dolphin with a living room slide out & a bed room slide out. The living room slide out I can get to the gears to clean & lube. But the bed room slide out is covered up inside & outside...
I also used a top brand of Carnuba wax that is for my black '88 Mustang, but it seems to work better on the car than under the slide. That's when I used the parafin and it does seem to last longer. You also might want to use it on the wood that the nylon pieces slide on. Little sandpaper, if you can get to the wood, and lots of parafin.