I have a 96 Grand Sport and when you remove the gas cap to fill I see corrosion/rust starting. How should I prevent that? I have in in my 01 Dodge Dooley also. Gas tank coating with a brush? Thanks!

 

John I don't know enough about the causes of rust inside the filler neck. However I can give you some information I learned from my 96 LT4 when I removed the filler neck to look onto the gas tank to see if there was any water in the tank. The way the drain trap is molded on my 96 it does no do an adequate job of keeping rain water/car washing water from getting down on the tank. The back of the drain trap I think should of exetended farther towards the front of the car. If you will remove yours you might see what I next mention. With the drain trap out you can see the perimeter of the filler neck and the indentions of the fuel lines in the filler neck. With the attachment of the filler neck to the tank, water can get around the perimeter of the filler neck and start rust and also water can get trapped in the indentions of the fuel lines. After installing my filler neck I took 3M strip chalk and lined the perimeter of the filler neck so it would not trap water. I then installed strip chalk into the indentions of the fuel lines to keep water from being trapped. Have not done it yet since I don't drive the LT4 much, but I am going to come up with something to install to assist the rear of the drain trap and keep the water from getting onto the tank.