I would 100% follow exactly what Pullrite says. I say that from a bad experience with them. Back in 2005-06 I had a hitch like yours, used the recommended silicone. Ended up with some major galling and head seperation. When I called PullRite I was told they had sent a newsletter stating that only dry graphite based lubricant should be used. I argued that a newsletter was not official correspondence and I had never received it, eventually they agreed to cover part of the costs to replace things, but not everything. In the end I changed rigs and lost my shorts on the hitch. So find out what hitch you have and find out exactly what they recommend. If you have one with the Delrin wear plate and blocks, use what they recommend, if not you may have issues and may not have warranty coverage.
Two Wire Fox Terriers; Sarge & Sully
2007 Winnebago Sightseer 35J
2020 Jeep Gladiator Rubicon