Caliper rebuild lubricant

I have been using "Silicon O-ring lube". The little tubes that come in the Spicer tranny overhaul kits, left over from the days I was working on RoadRangers.I put a "little" extra in the grooves.Havent seen any corrosion in there, in years.Available at your local jobber.
But yeah, brake fluid works. I wouldnt use anything petroleum based.I have seen them swell up pretty good/bad when the wrong stuff is used.