Go to the por-15 site and read about what that stuff can do. It does work as long as you do the prep work. I've been using it for years.

 

So dont sand the rust off the metal

 

They sell a metal prep that you spray on the rust, then rinse off. Then the por-15. Regular paint will not adhere to por-15, you have to use there tie coat primer.

 

Just clean it,get all you can off without taking it to the metal. My drive shaft was taken down really as far as you can take one down with a wire brush,but it still had a small coating of rust an it is holding up great,but the frame not so much.