Technically speaking anything other than Planet Eclipse Grease will void your warranty so I will throw that out there first.
I would personally recommend just buying a huge tube of Dow 33. It is the same as your planet eclipse grease (as far as I know) and can be bought in huge tubes at a great value. Most of the "aftermarket" lubes work fine as most of them are simply Dow 33 with added coloring/scents and a lot of hype. Generally speaking, none of these lubes perform any better then Dow 33 and some actually perform worse. Lurker Lube is a good Dow 33 alternative that has Teflon particles in it that can help protect the metal itself and make it slicker. I haven't used it on my Geo 3 but I have used it on other markers and it worked basically the same as Dow 33 with perhaps a slightly longer maintenance interval.
Last edited by Mr. Stealthy : 11-26-2013 at 12:49 PM.