I discovered Krown when stationed in North Dakota--it is good stuff in the right application. I still use it on my daily drivers.

It excels inside body panels in tight pinch-weld type of areas that tend to collect water and debris--on top of pickup truck rear wheel wells, inside doors especially on the bottom pinch weld where the skin meets the frame, rocker panels, trunk floor extensions and inner fenders where they meet the quarter panel.

It is not as good in large, open areas like the bottom of floor pans.

It does need re-applied occasionally.

As said above, an oily product that does not dry or harden is your bet bet IMO.