I used this on my 2016 Silverado to hopefully hold off body rot after having the rockers rusting through on my 2008 at 8yrs and 90k miles. My 2016 is at that same age and mileage and so far all is good.
Noxudol is a cavity wax that coats and creeps into the crevices and pinch welds. I sprayed it into the bottoms of the doors, rockers, tailgate, fenders, bedsides, and under the cab where there are braces spot welded to the floor. Every spring I pull out the fender liners and rocker panel plugs and flush everything out with water to hopefully get out the road salt hiding in the crevices.