I used Por-15 before. Its good on surface rust but it does nothing for 84-88 beds. I tried putting this stuff on my old truck and it still rusted. Any rust prevention paint should be tested in a midwest winter before being able to make the claims por-15 makes smile I am considered just getting a beater with a heater for winter driving. But then I think "I have a 4x4, whats the point in storing it away when I need it the most".