No one has attempted to answer your question, so I'll try and help by sharing what little I've learned.
I have a 20 year old HWH system that works great. I've lubricated the jacks with silicone spray (not WD-40)for over 10 years. My understanding is the WD-40 will react with the seals somehow, but I don't recall where I learned that warning. Apparently the silicone spray hasn't had any effect on my HWH system.
White grease is probably a very good lubricant, but may attract dust and dirt. I don't know about dry silicon.
Holiday Rambler Navigator DP, Hummer, and Honda VT1100C Shadow