Never a Dull moment for your Puppies? Very cool, keep on plugging away. I always liked the Military Engineer equipment.
Using zinc additive is a very good idea if the oil you are using does not have any, which most auto oils do not have any longer. Great thinking especially if the truck has been sitting, but do not use too much be a little economical or find a usage formula which some of our Heavy Truck Mechanics would have more knowledge than I.
Having worked in Heavy Equipment construction for a lot of years, 40 plus, we have from 25 ton cranes up to 550 ton mobile truck cranes.
Cosmoline on cable when new is for storage now but years ago that was the preferred method. Now there are spray can protectants with all kinds of formulas.
For winches that are in the mud or dirt after use I just unspool and mine having cosmo on inside anyway and rinse with water and spray down after drying with what ever is cheap. Teflon,
WD 40, graphite. As long as cable isn't frayed I may wipe with a thinned cosmo again and lay in sun to get to the interior.
I am positive that some of the Men on here have better applications, especially for the wreckers and retrievers.