Current information as of this posting from a phone call to Pullrite Superglide for the 16K with the latest design of the plastic wear plate, part #2700, use WD40 or 3 in 1 only. NO graphite or silicone used.
"Do not use any lubrication other than a light oil on the Way Tubes of your SuperGlide hitch. Using other lubricants, such as those with a silicone base, will create a residue and may hinder the functionality of the Turntable Cam Arm Assembly. Buildup of old oil and dirt can also create a residue over time and needs to be kept clean." Read more on their owner manuals online.