The benefit/cost ratio for a northern state DOT for corrosion management was estimated to be 4.4 by increasing corrosion management and focusing on proactive instead of reactive maintenance. More of interest to me was the corrosion management specifics, as I was looking at how to maintain my vehicle and keep it from rusting out. Specifically the following:
Periodically spraying a corrosion inhibitor (Krown T40, 19 times per year) would
effectively protect the aluminum, stainless steel, and carbon steel components on DOT equipment from corrosion related to NaCl or MgCl 2 deicers, by reducing their corrosion rate by at least 99%. Similarly, a one-time application of protective coating (Rust Bullet) reduced their corrosion rate by at least 99.5%, but additional research is needed to improve the integrity and durability of such coating over the years of field exposure.
Obviously a personal vehicle wouldn't need 19 applications a year, and some further research showed promise with using Noxudol brand spray coatings, which creep into crevasses and leave a waxy coating to keep water and salt off metal and reduce rusting. Probably somewhere in between the effectiveness of the Krown oil spray and the Rust Bullet paint researched in the studies. The issue I see with the paint is it would be great before rust started, but since I already have rust it probably wouldn't be as effective as something like an oil spray or Noxudol waxy coating. Noxudol is specified by several auto manufactures in rust related recalls, for the dealer to apply to the rust prone areas of the recalls and prevent further rusting, that plus personal usage antidotes I found point to this being close to the ideal for the average auto owner interested in keeping their vehicle from failing due to rusting out in northern areas with road salt usage.
